.NetBoy: SOME USEFUL FACTS OF ASP.NET

1. Development and Deployment Issues

1.1	Why are Server control tags shown in the browser instead of the controls it represents?

1.2	How To Repair ASP.Net IIS Mapping After You Remove and Reinstall IIS?

1.3	Why do I get "HTTP 500" error (or "(DLL) initialization routine failed") in my browser?

1.4	I have recently move my Web application from Windows 2k to Windows Server 2003. All works fine in Windows 2K but i am not able to view pages using Windows Server 2003?

1.5	What are the Best practices for side-by-side execution of Framework 1.0 and 1.1?

1.6	Can I have VS.NET and the Visual Studio 6.0 installed on the same machine?

1.7	How should I check whether IIS is installed or not?

1.8	In Visual Studio .NET, how do I create a new ASP.NET application for an existing ASP.NET project?

1.9	Why do I get the error message "Server Application Unavailable The web application you are attempting to access on this web server is currently unavailable. Please hit the "Refresh" button in your web browser to retry your request."?

1.10	In Visual Studio .NET, how do I create a new ASP.NET application which does not have a physical path under wwwroot?

1.11	Why do I get the "Unable to find script libruary 'WebUIValidation.js'" error ?

1.12	After installing .NET Framework SP1 the client side validations, or rather validator controls are not working?

1.13	How to Configure the ASP.NET Version to use for Each Application(developed using 1.0 or 1.1)?

1.14	How to Configure Different Versions of an ASP.NET Application Running on the Same Web Server?

1.15	Why do I get error message "Internet Explorer cannot download MyPage.aspx from MyWebSite.com ..."?

1.16	Why do I get error message "Unable to start debugging on the web server. The server does not support debugging of ASP.NET or ATL Server applications. ..."?

2. Basic

2.1	What is ASP.NET?

2.2	Why does my ASP.NET file have multiple tag with runat=server?

2.3	How to find out what version of ASP.NET I am using on my machine?

2.4	Is it possible to pass a querystring from an .asp page to aspx page?

2.5	How to comment out ASP.NET Tags?

2.6	What is a ViewState?

2.7	Where can I get the details on Migration of existing projects using various technologies to ASP.NET?

2.8	What is the equivalent of date() and time() in ASP.NET?

2.9	How to prevent a button from validating it's form?

2.10	How to get the IP address of the host accessing my site?

2.11	How to access the Parameters passed in via the URL?

2.12	How to Set Focus to Web Form Controls By Using Client-Side Script?

2.13	How to display a Wait page while a query is running?

2.14	How to implement Form based Authentication in ASP.NET application?

2.15	How to catch the 404 error in my web application and provide more useful information?

2.16	Is there a method similar to Response.Redirect that will send variables to the destination page other than using a query string or the post method?

2.17	What are the differences between HTML versus Server Control?

2.18	How can I change the action of a form through code?

2.19	Is there any control that allows user to select a time from a clock - in other words is there a clock control?

2.20	How to Compare time?

2.21	How To work with TimeSpan Class?

2.22	Where can I get information on Cookies in ASP.NET?

2.23	Does ASP.Net still recognize the global.asa file?

2.24	How should I destroy my objects in ASP.Net?

2.25	Are there resources online with tips on ASP to ASP.Net conversions?

2.26	How do I publish my ASP.NET application to my ISP's web server?

2.27	Why do i get error message "Could not load type" whenever I browse to my ASP.NET web site?

2.28	Will the WebMatrix SqlDataSourceControl work with a MySQL connection?

2.29	Can I combine classic ASP and ASP.NET pages?

2.30	What is the difference between src and Code-Behind?

2.31	How can I get the value of input box with type hidden in code-behind?

2.32	I have created a .NET user control page (.ascx) but I cannot compile and run it.

2.33	What is a .resx file?

2.34	Is it possible to use a style sheet class directly on a control instead of using inline or page-level formatting ?

2.35	Can I recieve both HTML markup for page and code in the ASP.NET web page's source code portion in the Web browser?

2.36	Why can't I put <%@ Page Language="C " %> where at the top of an ASPX file and write my server-side scripts in C ?

2.37	ASP pages that worked pefectly on Windows 2000 Server and IIS 5.0 do not work on Windows 2003 Server with IIS 6.0. ASP.NET pages work fine. Why?

2.38	Why do I get error message "Error creating assembly manifest: Error reading key file 'key.snk' -- The system cannot find the file specified"?

2.39	How to get URL without querystring?

2.40	What is the best way to output only time and not Date?

2.41	Do I have to compile code if I am changing the content of my aspx.cs file?

2.42	How to grab the referring URL?

2.43	My ASP code gives an error "Compiler Error Message: BC30289: Statement cannot appear within a method body. End of method assumed" when changed to .aspx?

2.44	How can I save images ?

2.45	How can I logout when using FormsAuthentication?

2.46	Why do I get a blank page when I use Server.Transfer ("page1.htm") to transfer to a different page?

2.47	How to detect the User's culture?

2.48	What is the difference between CurrentCulture property and the CurrentUICulture property?

2.49	Can I read the hard disk serial # of the client computer using ASP.NET?

2.50	What is xxx(src As Object, e As EventArgs)?

2.51	What is the difference between Absolute vs Relative URLs?

2.52	What is the difference between URL and URI?

2.53	How to convert milliseconds into time?

2.54	How to include multiple vb/cs files in the source?

2.55	How to convert a string to Proper Case?

2.56	How can I ensure that application-level variables are not updated by more than one user simultaneously?

2.57	Why do I get the error message "System.InvalidOperation Exception: It is invalid to show a modal dialog or form when the application is not running in UserInteractive mode. Specify the ServiceNotification or DefaultDesktopOnly style to display a ...."?

2.58	How to validate that a string is a valid date?

2.59	Are namespaces and Class names Case Sensitive?

2.60	How to convert string to a DateTime and compare it with another DateTime?

2.61	How to get the url of page dynamically?

2.62	How to convert user input in dMy format to Mdy?

2.63	When the User is prompted a File Download dialogbox, if the user selects "Save" then the "Save as" dialog box is displayed. Is there any way for me to retrieve the filename and directory path specified by the user on the File Download dialog box?

2.64	How to hide or show Controls in server side code?

2.65	How to check if the user is using a secure or non secure connection?

2.66	Is it possible to write code in many languages in one ASP.NET project?

2.67	What is the difference between Response.Redirect() and Server.Transfer().

2.68	How to get the hostname or IP address of the server?

2.69	What is the meaning of validateRequest=true in .net framework1.1?

2.70	What is the different between <%# %> and <%= %>?

2.71	What permissions do ASP.NET applications posses by default?

2.72	How can I specify the relative path for a file?

2.73	How can I specify the "upload a file" input textbox in a form to be read only so that the user can click on the browse button and pick a file but they cannot type anything into the textbox next to the browse button.

2.74	How to change the Page Title dynamically?

2.75	Why do I get the error message "Object must implement IConvertible". How can I resolve it?

2.76	Why is default.aspx page not opened if i specify http://localhost. I am able to view this page if i hardcode it as http://localhost/default.aspx?

2.77	Can ASP.NET work on an NT server?

2.78	Is it possible to migrate Visual InterDev Design-Time Controls to ASP.NET?

2.79	How to automatically get the latest version of all the asp.net solution items from Source Safe when opening the solution?

2.80	How to convert the datetime into a string for use in the SQL ' statement?

2.81	How to make VS.Net use FlowLayout as the default layout rather than the GridLayout?

2.82	Can I use a DataReader to update/insert/delete a record?

2.83	What is the difference between Server.Transfer and Server.Execute?

2.84	How to create a login screen in ASP.NET?

2.85	How to format a Telphone number in the xxx-xxx-xxxx format?

2.86	Can two different programming languages be mixed in a single ASPX file?

2.87	Can I use custom .NET data types in a Web form?

2.88	How can I have a particular Web page in an ASP.NET application which displays its own error page.

3. Debugging and Error Handling

3.1	Why do I get Error message "Unable to Start Debugging" Error Message When You Send Debug HTTP Request?

3.2	Why do I get the error message "Unable to start debugging on the web server..." when I debug?

3.3	When I Debug ASP.NET Applications I get error message "Access Is Denied. Check the DCOM Configuration Settings for the Machine Debug Manager"?

3.4	On Trying to Debug an application, by the F5 key I get the error: "Error while trying to run project: Unable to start debugging on the web server. Catastrophic failure"?

3.5	How to configure my project for debugging ASP Code?

3.6	In Visual Studio .NET, whenever I try to debug my ASP.NET application I'm not able to stop the debugger on my breakpoints. Why?

3.7	Why do I get error message "Unable to start debugging on the web server. The debugger is not properly installed. Run setup to install or repair the debugger. Would you like to disable future attempts to debug ASP.NET pages for this project ? "?

3.8	How do I debug JavaScript and other script code in my application using Visual Studio .Net?

3.9	What are the different exception-handling approaches that can be used in ASP.NET?

3.10	Why do I get error message "Login failed for user '(null)'. Reason: Not associated with a trusted SQL Server connection"?

3.11	Why do I get the Error Message "System.OutOfMemoryException: Exception of type System.OutOfMemoryException was thrown."?

3.12	Why do I get the error message "Sql Server does not exists or access denied " whenever I try to access the data on Sql server?

3.13	Why do I get error message "It is already opened exclusively by another user, or you need permission to view its data." when I try to open Access mdb?

3.14	Why do I get the "HTTP 404 - File not found." error message as "The page cannot be found.The page you are looking for might have been removed, had its name changed, or is temporarily unavailable "?

3.15	When I install the Microsoft .NET Framework 1.1 on a computer that is running Windows XP, and then you start Windows, the Welcome screen appears. This screen prompts me to click your user name to start Windows.Why?

3.16	Why do I get the error message "System.InvalidOperationException: Application is restarting"?

3.17	How can I see the Trace messages?

3.18	I have installed ASP.NET hotfix and I find that Startup Type of the ASP.NET Session State Service is set to Manual.Why?

3.19	Why do I get the error message "aspnet_wp.exe (PID: XXXX) was recycled because it was suspected to be in a deadlocked state "?

3.20	How to display errors using Page_Error event of Page Object?

3.21	How to redirect the user to the friendly error-handler page when an Application error occurs?

3.22	How to Enable Remote Debugging on Windows XP Service Pack 2?

3.23	Why do I get error message ""Parser Error Message: Access is denied: Source Error: Line xxx : ""?

3.24	Why do I get the error message "A potentially dangerous Request.Form value was detected from the client "?

3.25	How can I test performance of the Web application?

3.26	How can I resolve the error message "Cannot access file '...' because it is being used by another process"?

3.27	Why do I get the Compiler Error Message: "CS0246: The type or namespace name '...' could not be found (are you missing a using directive or an assembly reference?) "?

3.28	Why do I get the error message "Compiler Error Message: CS1595"?

3.29	I get error message at runtime "Value null was found where an instance of an object was required" when using Application state variables. why?

3.30	I installed Windows 2003 Standard Edition, then VS.NET and SQL Server 2K with SP3. When I build web project connecting to the database in VS.NET, the compliler gives me the following error:Login failed for user 'NT AUTHORITY\NETWORK SERVICE',why?

3.31	Why do I get error message "System.Threading.ThreadAbortException: Thread was being aborted" while using Response.Redirect?

3.32	Why do I get the error message "BC30451: Name 'ConfigurationSettings' is not declared"?

3.33	What is a parser error?

3.34	Whenever I browse to one of my ASP.NET web pages, Internet Explorer keeps on asking me if I want to download it, or it just displays the ASPX source. Why?

3.35	Why am I getting the error: "Type '(OleDb or SQL)Connection' is not defined."?

3.36	Why do I get the Error message "Operation must use an updateable query"?

3.37	When compiling I get "Could not copy temporary files to the output directory" or "The process cannot access the file because it is being used by another process" error messages. Why?

3.38	Why do I get error message "Failed to Start Monitoring Directory Changes" when i try to browse ASP.NET page?

3.39	Why do I get Compilation error " is not a member of "?

3.40	How to see the Message in the Output window using ASP.NET?

3.41	How can I use Tracing in Custom Components?

4. Miscellaneous

4.1	How to get the currently logged in user?

4.2	How to specify a line break in a Label's Text?

4.3	How to convert a string to HTML format?

4.4	How do I determine if the user clicked a "Submit" button twice in the page?

4.5	How to write date-time values of fields in a dataset into xml in a specific format?

4.6	What does "~" mean in ASP.NET applications?

4.7	How can I reference simple DLL which contains one class but has no namespace assigned to it in an .aspx page?

4.8	How do I specify the Japanese locale for the controls in my Japanese localized page?

4.9	Why do some of the events on my page fire twice?

4.10	How to remove the spaces in a given string?

4.11	I get the error System.__ComObject when using recordset?

4.12	Why do I get error "A generic error occurred in GDI+." when trying to save the bitmap file?

4.13	How can I force a Save As dialog box from an ASP.NET Web page.

4.14	In ASP.NET is there a control similar to Combobox in Windows forms?

4.15	How to do text encryption and decryption?

4.16	How can I trigger a submit on my form when the enter key is pressed?

4.17	How to get list of all files in the directory?

4.18	What is HttpHandler?

4.19	How to get the size of a byte array?

4.20	How to know the width and height in pixels of a given image programmatically?

4.21	When using FormsAuthentication, how can I redirect a user to a different page other than the default page?

4.22	Is there a control in ASP.NET for geting HTML like the ASPHTTP for the classic asp.

4.23	Why do I get error message "System.Web.HttpException: Request is not available in this context" " when using Cookies?

4.24	How to save the Output of ASP.NET to HTML?

4.25	Why do I get ViewState error when upgrading my application from a single web server to a web farm?

4.26	How to convert Color to it's corresponding Hexadecimal value?

4.27	How to Select a record using Listbox and edit/update it's fields using textboxes?

4.28	How to select a value from a child form and send it to parent form?

4.29	How to read the comma seperated values from a string?

4.30	How do I make my TextBox positioned below a DataGrid move up or down in position as the height of the DataGrid changes?

4.31	How to stamp Date-Time on all the pages in an application when requested?

4.32	How can I have multiple command buttons map to the same event or function?

4.33	How to use a RangeValidator to select Colors from a specific range?

4.34	How to restore the browser's scroll position after a postback?

4.35	Is there something as RecordSet we had in ASP that can be used in ASP.NET?

4.36	How to set a link tag's href attribute at runtime using a value specified in the web.config file?

4.37	How to call the Page_load procedure from any event on the page?

4.38	How to add login user (ASPNET) to MS SQL 2000 Desktop Engine server?

4.39	How to get the count of rows in a Excel file?

4.40	What are the pros and cons of using Session or Cache to save intermediate state?

4.41	How to mirror (align elements Right to Left) a form or control on a form?

4.42	How can I Enable ASPX Compression in IIS?

4.43	How to run an exe from a ASP.NET page?

4.44	Why does FormsAuthentication.Decrypt crashes when moving to another Server?

4.45	Why do I get error message "Login failed for user DOMAIN\USERNAME"?

4.46	How to check if the current User has been Authenticated?

4.47	How to get the Computer Name on which the code is running?

4.48	How to pass argument to accessdatasourcecontrol selectcommand statement?

4.49	How to compile CS/VB file and place new DLL in bin subdirectory?

4.50	Can I use a src attribute with a Web Service?

4.51	How to display random images on a web page from a set of images in a directory?

4.52	How can I scan a string to determine if it contains DBCS chars?

4.53	Request.ServerVariables("LOGON_USER") always returns empty string in Framework 1.1 . Why? It worked fine in ASP?

4.54	Is there a way to specify CSS only if the browser is IE?

4.55	How to create Custom Application Settings in the web.config?

4.56	Why do I get "do not have permissions" error when accessing a Access mdb file in my local system?

4.57	How can I access an MS Access database in my ASPX page, if the db is on a remote server?

5. Calendar

5.1	How to display multiple dates selected in Calendar Control?

5.2	How to reset the selected date in the calendar control?

5.3	How to Customize Individual Days in a Calendar Web Server Control?

5.4	Is there a way to click an image and let the calendar Control appear?

5.5	How to Programmatically change backgroundcolor of a Calendar Control using Dropdown List?

5.6	How can I change the month and Weekdays to Japanese characters for a Calendar Control?

5.7	How can I use a Calendar Control to show specific dates highlighted and display relevant data for that date?

5.8	How to clear the Calendar Control Selection?

5.9	How can I set the Selection of the Calendar Control to date or week or month?

5.10	How can I display the calendar control in different languages according to the navigator culture?

5.11	How to display full day names in a Calendar Control?

5.12	How to hide the WeekDay Header in the Calendar control?

5.13	How to hide "other months" in a Calendar Control?

5.14	How to highlight today's date in Calendar Control in different color?

5.15	How can I use a Calendar Control in readonly mode. i.e no links for the day and month cells.

5.16	How to change the Calendar Dates using a Dropdownlist?

6. User Controls

6.1	How can I include an Asp.NET page in many other Asp.Net pages so that I don't need to rewrite the code?

6.2	Is there anything similar to web templates in ASP that I can use in ASP.Net?

6.3	Are there any settings on the application level to make certain elements appear on every page without having to manually insert code or insert UserControls?

6.4	How to pass a parameter to a user control?

6.5	How to add user control dynamically into another usercontrol?

6.6	I have a function inside of the .ascx file. How can I call it from the web application page(the .aspx file)?

6.7	How to dynamically load User Controls?

6.8	How to change the imageurl of the image control that exists in a usercontrol?

7. DataList

7.1	Why is the DataList not displayed on the web page?

7.2	How to change the colors of a row to indicate its the Birthday of the Employee (for example) in a DataList?

7.3	How to group the data in the DataList?

7.4	Which control should I use when binding a multidimensional array?

7.5	How to display data in multiple columns for a specific Column in a table in an ASP.NET page?

7.6	How to use a Hyperlink in a DataList?

7.7	How to do Paging in DataList?

7.8	How to hide and show data in the DataList?

7.9	How to add a Templatecolumn dynamically to a DataList?

7.10	How to create a File Picker in ASP.NET?

7.11	How can I get a list of all the environment variables?

7.12	How to display checkbox in a DataList and highlight a row if the value of checkbox is true?

7.13	How to display all System Colors in a DataList?

8. Repeater

8.1	How to display alphabetically sorted data in Repeater?

8.2	How to display the Directory names in the Repeater Control?

8.3	How to define HeaderTemplate and ItemTemplate to the Repeater at runtime TBD?

8.4	How to add a TemplateColumn dynamically to Repeater?

8.5	How to implement sorting using Repeater?

8.6	Can I specify ItemStyle to a Repeater Control?

8.7	How to change the row color of the Repeater based on some condition?

9. Security

9.1	What is the difference between authentication and authorization?

9.2	How to implement authentication via web.config?

9.3	How to run a Web application using the permission of an authenticated user?

9.4	Which are the different ASP.NET authentication modes?

9.5	How to determine the Windows User from a Web form Application?

9.6	After installing SP4 none of my ASP.NET pages developed using Framework 1.0 are showing the errors related to security?

10. CheckBox

10.1	How to assign a text to Checkbox control and know which checkbox is selected?

10.2	How to validate a CheckBox?

11. Client Side Scripting

11.1	How to emit client-side javascript blocks from VB.NET/C#?

11.2	How to open a new Window using javascript function from a Link button?

11.3	Is there a JavaScript Quick Reference Guide?

11.4	How to set the background color of a web page using code behind?

11.5	How to resolve error message "String constants must end with a double quote."?

11.6	Why can't I open a new browser window from within server code?

11.7	How to get the confirmation of Yes/No from a javascript pop-up and display the value on the page?

11.8	How to open a browser window with maximum size on click of a button?

11.9	How can I know if the client browser supports active scripting?

11.10

How to determine if the Browser supports javascript?

11.11

How can I change the scroll bar color?

11.12

How to create dynamic javascripts in server side code based on server side variables?

11.13

How can I use a Timer Control to refresh a page automatically at a specified interval?

11.14

How to open a new window without IE menus and toolbars on click of a button?

11.15

Does JavaScript support hashtables/ hash tables or dictionary type data structures?

11.16

How to disable the right click option on a web page?

11.17

How to hide a control using javascript?

11.18

Can I modify WebUIValidation.js?

11.19

How to change a Label element's text in javascript?

11.20

How to resize two

tags on a webform?

11.21

How to check/ uncheck a checkbox based on the text entered in textbox?

11.22

How to rotate a Label Text?

11.23

How to display a message in the status bar of a browser window?

11.24

How to change the BackGroundColor of a page based on the value selected in a DropdownList?

11.25

How to disable a Dropdownlist once someone has selected an item in the Dropdownlist?

11.26

How can I make a Textbox a mandatory field if a checkbox is checked on a button click event in the client side?

11.27

Why does the SmartNavigation does not work on the live server but works perfectly on the Development Machine?

11.28

How to pop up a message box when no item in the dropdownlist is selected before postback?

11.29

Are there any resources regarding the Mozilla specific Browser Objects and CSS information?

12. XML

12.1	How to write the data from database into an XML file?

12.2	How to read data from an XML file and display it in a DataGrid?

12.3	How to read data from the XML file using FileStream and display it in a DataGrid?

12.4	How to save an xml-string into an Xml document?

12.5	How to use the tag?

12.6	How to display the Attribute values in an XML Document in a DataGrid?

13. CheckBoxList

13.1	How to retrieve the multiple selected items in a CheckBoxList?

13.2	How to check if nothing is selected in a CheckBoxList without using a loop to parse through all the items?

14. AdRotator

14.1	How to use an AdRotator in ASP.NET?

14.2	Why do I get a blank image when I set the KeywordFilter property of the AdRotator?

14.3	How to extract the information between the ImageUrl of an Advertisement file?

15. Files

15.1	What is the best way to rename a file on the webserver in code?

15.2	How to create a folder in ASP.NET?

15.3	How to show the ASP.NET code to the users?

15.4	How to read a html file in ASP.NET?

15.5	How can I to get the path to the system area that holds temporary files?

15.6	How to save a file in the client machine?

15.7	How to get the physical path of a file?

15.8	How to get the current filename?

15.9	How to Upload files in ASP.NET?

15.10

How to delete a file from the server?

15.11

How to find the date and time the specified file or directory was last written to?

15.12

How to get the File information using ASP.NET?

15.13

How to create a .csv file that grabs the data from the database?

15.14

How to read text file in ASP.NET?

15.15

How to read specific characters from a text file?

15.16

How to check files exist in a particular directory?

15.17

What is a MemoryStream and how to use MemoryStream in ASP.NET?

15.18

How to detect if the string indicating a file-system resource is a file or directory?

16. ListBox

16.1	How to make the listbox scroll down to show it's last entry when the page loads?

16.2	How to check if an item already exists in a listbox?

16.3	How to populate a listbox with the Column Names in a Table?

16.4	How to clear all the items in a listbox?

16.5	How to add items dynamically to a ListBox using an ArrayList?

16.6	How to move items between ListBoxes?

16.7	How to select a specific Item in a ListBox in code?

16.8	How can you use a ListBox control to display items with Price above a specific value in one color and the ones below that value in a different color?

16.9	How to select all the Items from a listbox when the user selects a radio button?

16.10

How to use a single DataReader associated with two different tables to databind two different listbox controls?

17. Output Caching

17.1	How can I remove the cache of a page (cached with VaryByParam) for certain request params in code?

17.2	How can I set a page/control to be cached only for certain parameters?

17.3	What is Output Caching?

17.4	I want to Cache based on HTTP header .How can I do that?

17.5	How to make a page expire immediately in such a way that a warning message "This page has expired."appears?

17.6	How to prevent client Cache? I want every client request get sent to the server even if it's behind a proxy server and for any browser setting.

17.7	Is there any way to cache by browser a page or User Control?

17.8	Is caching PDF Files a good or bad idea?

17.9	How to remove Output Cache by param?

17.10

How can I programatically invalidate the outputcache from a usercontrol?

17.11

Is it possible to cache a page by Browser Version and/or some params?

17.12

Why do I get the error message "The type or namespace name 'CacheDependency' could not be found (are you missing a using directive or an assembly reference?) "?

17.13

Is there a way that I can clear/expire a page cache from another page/class?

17.14

How to access the Cache from a compiled class?

17.15

How can I cache the page by the complete querystring?

17.16

How do I access the cache in the Global.asax?

17.17

How to display items stored in a local application Cache?

17.18

Is there a Cache.RemoveAll()? How can I clear / remove the total cache?

17.19

Why do I get the error message "Exception Details: System.Web.HttpException: Cache is not available "?

17.20

How to remove the Cache starting with "cachedata_"?

18. Mail

18.1	How to send HTML mail in ASP.NET?

18.2	How to send simple text mail in ASP.NET?

18.3	What is the namespace used for sending mails?

18.4	How do I configure a local SMTP server?

18.5	Why do I get the error message "The transport failed to connect to the server "?

18.6	Why do I get the error message "The SendUsing configuration value is invalid"?

18.7	How can I read POP3 email with ASP.NET?

18.8	How do I email a website exception?

18.9	How do I send a web page?

18.10

How do I send non US-ASCII mails?

18.11

How do I send an email with attachments?

18.12

How do I add the Reply-To header to the MailMessage?

18.13

Why do I get the error message "Sender address rejected: need fully-qualified address "?

18.14

How do I resolve the error "The server rejected one or more recipient addresses. The server response was: 503 This mail server requires authentication. Please check your mail client settings"?

18.15

How can I specify multiple recipients for a message?

18.16

How can I use a "friendly name" in the To and From properties?

18.17

Why do I get the error message "550 5.7.1 Unable to relay for xxx or 550 not local host xxx, not a gateway "?

19. GDI+

19.1	Why do I get the error message "CS0122: 'System.Drawing.Imaging.ImageFormat.jpeg' is inaccessible due to its protection level "?

19.2	Why do I get the error message "A generic error occurred in GDI+."?

19.3	How to draw strings vertically on a Bitmap?

19.4	I am using GDI+ to write on a bitmap. I know how to make font Italic/Bold. What should be done to apply both Italic and Bold?

19.5	How can I display image from a Sql Server database?

19.6	How to display image on a browser without using the image tag?

19.7	How to rotate a image in ASP.NET?

19.8	How to show the graphics that have text written on it crisp and clear?

19.9	I get error "Value of String cannot be converted System.Drawing.Color' when I use label1.BackColor= "Red"?

19.10

How to load a image from a website URL?

19.11

How can I check the image raw format i.e how can I find if Image.RawFormat property returns a "jpeg" or "gif",?

19.12

How to align the text on a bitmap?

20. Collections and Lists

20.1	How to bind an ArrayList to a DropDownList?

20.2	How to check if the ArrayList is empty?

20.3	I get the error message "DataGrid with id 'DataGrid1' could not automatically generate any columns from the selected data source" when I bind a HashTable to the DataGrid?

20.4	How to sort ArrayList?

20.5	How to sort the DataGrid using an ArrayList as the DataSource?

21. RadioButton

21.1	How can I have the first item in the radiobuttonlist selected?

21.2	What is the difference between a series of RadioButton controls and a series of Checkbox controls?

21.3	How can I enforce that only one radiobutton gets selected among a list of Radiobutton controls?

22. Controls

22.1	How to close the browser window on button control click?

22.2	How to create server controls at runtime?

22.3	How to change the text color of a linkbutton control?

22.4	How to dynamically add validator controls?

22.5	How to change the image button size during runtime?

22.6	How can I to divide the .aspx page to different parts with different functionality in a neat and organized manner. Is there any control that can do that?

22.7	How to maintain Scroll Position in any Page Element?

22.8	DataBinder.Eval imposes performance penalty on code as it uses late bound reflection. How can I replace this calls with explicit calls?

22.9	What is the difference between User Controls and Custom Controls?

22.10

How to apply Style to a Web Server control programmatically?

22.11

How can I disable a button to prevent the user from multiple clicking?

22.12

Why do I get the error message "Access is denied : " when I try to load a Custom Control?

22.13

How to pass information between panels. Information entered in one panel should be displayed in other panel?

22.14

Why do I get error message "The control '_ctl1' of type 'TextBox' must be inside a form label with runat=server" while trying to place a control inside a form dynamically?

22.15

How to implement mouseover effects in a web server control?

22.16

Is there a way to set the position of the controls dynamically?

22.17

How can I set the maximum and minimum value for RangeValidator based on two dates?

22.18

How to specifiy the hspace and vspace in a ?

22.19

How to disable status bar messages for Hyperlink Controls?

22.20

How to get the list of all System.Web.UI.WebControls in my page?

22.21

How to set the vertical align of a TableCell programmatically?

22.22

How to control viewstate on individual controls?

23. Table Control

23.1	How to create a table control dynamically to populate data?

23.2	How to limit table cell size with long strings?

23.3	How to use a Table control to display data vertically?

23.4	Are there any IE specific performance imporvement possible with Table Layout?

24. CSS Styles

24.1	Why does my page show up poorly in Mozilla based browsers like Netscape and Firefox?

25. DataGrid

25.1	Why do I get the Columns twice in the datagrid. I am using BoundColumns and TemplateColumns in DataGrid?

25.2	How to Format and display currency with n decimal points in a BoundColumn.

25.3	How do I specify more than one parameter for my HyperlinkColumn?

25.4	Why am I getting an 'AllowCustomPaging must be true and VirtualItemCount must be set for a DataGrid with ID MyDataGrid when AllowPaging is set to true and the selected datasource does not implement ICollection' Error?

25.5	How do I use a "helper function" to change the column value as Boolean in database to be displayed as Yes/No in Datagrid?

25.6	How to display only date part in the Datagrid if the Date is of DateTime datatype in the database?

25.7	How to open a new window with multiple parameters when clicked on a hyperlink in a column in a datagrid?

25.8	How to display hierarchical data in a DataGrid?

25.9	How do I conditionally set the text color of a cell in my Datagrid based on the cell's/fields's value?

25.10

When I open my new window using Javascript, all elements appear great, but the original window just displays [Object] why?

25.11

How to populate a DataGrid using a DataReader?

25.12

How to populate a DataGrid using a DataSet?

25.13

Why do I get "Could not lock file" and "cannot open file" exceptions when bound to a mdb file?

25.14

I am binding the DataGrid to a datasource at runtime. After binding I want to populate a listbox with the column headers from the datagrid. How can I reference the column headertext for each column in the datagrid and then add them to my listbox?

25.15

When I try to do an Update from my Datagrid, I keep getting the old/original values. Why?

25.16

How can I sort a BoundColumn?

25.17

How can I hide the HeaderText of the DataGrid?

25.18

How to add a mailto link inside a datagrid?

25.19

How to do Simple sorting using DataGrid?

25.20

How to do Paging using DataGrid?

25.21

How to display an image field in each row of DataGrid?

25.22

How to get the DataField name of a BoundColumn from code-behind?

25.23

How to confirm delete in DataGrid using PushButton?

25.24

How to do Bidirectional Sorting in the DataGrid?

25.25

How to have mutually exclusive radiobutton controls in a datagrid.

25.26

How to add a TemplateColumn dynamically to the datagrid?

25.27

How to edit data in the DataGrid using a TemplateColumn?

25.28

How do I use Validator controls while editing data in the DataGrid?

25.29

How to highlight the Column that is sorted in a DataGrid?

25.30

How to create a Drilldown DataGrid?

25.31

How to set a Datagrid Column to invisible when that Column is an AutoGeneratedColumn?

25.32

How to use the DataFormatString to format DataGrid data dynamically?

25.33

How to set the maxlength of a textbox (in the EditTemplate of DataGrid) based on a field value in the record?

25.34

How to add an attribute to the Table generated by the DataGrid?

25.35

Why do I get the error message " CS1502: The best overloaded method match for 'xxx(string)' has some invalid arguments " when I use Helper function in DataGrid?

25.36

How to confirm delete in DataGrid using LinkButton?

25.37

How to hide and show a Column based on the authenticated user?

25.38

How to use a dropdownlist in a DataGrid?

25.39

How to set a different color for every alternate row of a datagrid?

25.40

How to add a counter column to a DataGrid?

25.41

How to change the HeaderText of the Datagrid?

25.42

How to select a record in the datagrid and start editing/updating the record using textboxes?

25.43

How can I show what page the user is on using in-built paging functionality. CurrentPageIndex Property Shows Up as 0?

25.44

How to display "No data" when a field value is null?

25.45

How to change the value of a field before it gets displayed in the datagrid?

25.46

How to use a ButtonColumn in a DataGrid?

25.47

How to display a Master Detail data using DataGrid?

25.48

I have set the ItemStyle and the AlternatingItemStyle tags for DataGrid control but they aren't working correctly , why?

25.49

How to display the checkbox checked or unchecked for a bit data type value in the DataBase?

25.50

How to do alphabetical paging in ASP.NET?

25.51

How to enable or disable the button in the DataGrid based on a bit value in the database?

25.52

How to show data vertically in a datagrid for a particular row?

25.53

How can I fix error message "Invalid CurrentPageIndex value. It must be >= 0 and <>

25.54

How to edit a record using DataGrid?

25.55

How to delete a record using DataGrid?

25.56

How to use a HyperlinkColumn for a DataGrid?

25.57

How to use a LinkButton in a DataGrid?

25.58

How can I display the field as a link in the DataGrid? If may or may not be stored in the "http://" format.

25.59

How to hide a column in a Datagrid if AutoGenerateColumns is set to True?

25.60

How do I change the width of the Textboxes created for edit-mode of a Datagrid?

25.61

How to display a Tooltip when hovering over the Header sort link of the DataGrid?

25.62

How to right align cells in the Datagrid when using BoundColumn?

25.63

How to hide a row in a DataGrid if one of the Column value is zero?

25.64

How can I disable sorting for a specific Column in a DataGrid?

25.65

Why do I get error message "NewPageIndex is not a member of "System.EventArgs"."?

25.66

How to create a Main Header in DataGrid along with the DataGrid Column Headers?

25.67

Is there a way to show more than one datafield in a column when using a datagrid?

25.68

How to databind a textbox in a column template that is inside a datagrid?

25.69

How can I simulate a scrollbar in a DataGrid?

25.70

How to clear a DataGrid?

25.71

How to trigger the checkChanged event of the checkbox inside a DataGrid?

25.72

How to display "No data exists" within the datagrid rather than just showing Column Headers with no rows?

25.73

How to fill a DataGrid with an array?

25.74

How to add a Column dynamically to the datagrid to include custom expressions?

25.75

How to access the BoundColumn information on SelectedIndexChanged event of a datagrid?

25.76

How to access the TemplateColumn information on SelectedIndexChanged event of a datagrid?

25.77

How to access information from the controls in the TemplateColumn in SelectedIndexChanged Event?

25.78

How to display the total of a particular column at the footer of the DataGrid?

25.79

Why does the DataGrid web server control contents wrap when ItemStyle Wrap or HeaderStyle Wrap Property is set to False?

25.80

How can I have an onclick event in the DataGrid for any Column?

25.81

How should I avoid getting blank page on click of linkbutton inspite of setting the EnableViewState= true for DataGrid?

25.82

Why do I get a blank page when I click the linkbutton in the Datagrid, I am also handling PostBack on the page? The ItemCommand Event does not seem to trigger?

25.83

How to export data in Datagrid on a webform to Microsoft Excel?

25.84

How to export DataGrid data to excel?

26. Design Time Serialization

26.1	Why doesn't my properties tagged with the PersistenceMode.InnerProperty attribute get saved in the aspx file?

26.2	Why doesn't changes made to some of my properties don't get saved in the aspx file during design time?

26.3	Why doesn't my Collection Properties get saved in the aspx file properly during design-time?

27. Custom Controls

27.1	How do I insert custom @ Register tags into the aspx file from my custom control?

28. TextBox

28.1	How to cast the value entered in a textbox to integer?

28.2	How to allow only numeric values in a textbox using ASP.NET Validator control?

28.3	Why does TextBox retain its values when posting inspite of having ViewState property disabled for TextBox,?

28.4	I am running the query SQL="Select name from profile where proID=1"; and I am getting the result in Dataset dsdata. How can I read the text from the dataset and assign it to textbox1.text ?

28.5	How to align the Text property of the Textbox Control?

28.6	Why do I get error message "Option Strict On disallows implicit conversions from 'System.Web.UI.Control' to 'System.Web.UI.WebControls.TextBox'."?

28.7	How to convert TextBox value into a DateTime variable?

28.8	How to clear all the textboxes in my form?

28.9	How to programmatically set the width of the textbox control?

28.10

How to get the textbox value at the client side ?

28.11

How to display data in Textboxes using DataSet?

28.12

How to display data in Textboxes using DataReader?

28.13

Is there a TextArea in ASP.NET?

28.14

How to right align the text in the TextBox?

28.15

How to force the max no. of lines in a multiline TextBox using RegularExpressionValidator?

28.16

How to change server control backcolor from a variable?

28.17

How to create an array of Web Controls?

28.18

How to show TextBox web server control with TextMode Property Password as **** rather than blank?

29. Dropdownlist

29.1	I have 3 DropDownLists on the page : one for a Month, second one for a Day, and the last one for a Year. How can I let the user choose the data and enter it to 'datetime' column in the database.

29.2	How to apply css style to each item of the dropdownlist or listbox control?

29.3	How to concate and display 2 fields in a dropdownlist?

29.4	I have a page with a Dropdownlist and some simple code for the SelectedIndexChanged but it does not do a postback?

29.5	How to add an extra item to the DropDownList filled with data from a database?

29.6	Can I use a dropdownlist to allow user to select multiple items from a list of available items?

29.7	Why do I get System.Data.DataRowView/System.Data.Common.DbDataRecord as the item in a dropdownlist?

29.8	How can I display a Tool tip for a dropdownlist?

29.9	How to select a specific Item in a DropDownList?

29.10

How to display multiple spaces in a dropdownlist?

30. Config files

30.1	What is the best place to store Database connection string?

30.2	My web.config gives error "Unrecognized attribute 'verb'."?

30.3	Can I use IIS as an alternative way of configuring Custom error pages?

31. ADO.NET

31.1	What is the Performance comparison between DataSet and DataReader?

31.2	How to get the count of records in the Database table using the DataSet?

31.3	How to check if the Dataset has records?

31.4	How to retrieve value of a field in a dataset?

31.5	How to filter the data in the DataView and display it in some DataControl?

31.6	How to truncate the data in the column?

31.7	How to find the null fields in the datareader?

31.8	How to Implement a DataSet SELECT DISTINCT Helper Class?

31.9	I am running the query SQL="Select name from profile where proID=1"; and I am getting the result in Dataset dsdata. Now how do I read the text from the dataset and assign it to textbox1.text ?

31.10

How to query the database to get all the Table names?

31.11

How to View one record per page in ASP.NET?

31.12

How to insert data in database using Textboxes?

31.13

When I try to enter a null value for DataTime in Database I get error message "String was not recognized as a valid DateTime" or "Value of type 'System.DBNull' cannot be converted to 'String'"?

31.14

How to use Parameterized queries in ASP.NET?

31.15

How to filter distinct records from a normal Select query and display in a web control?