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Displaying an Image from a Database in a Web Forms Control

[ Team LiB ] Recipe 7.7 Displaying an Image from a Database in a Web Forms Control Problem You need to display an image from a database column in an ASP.NET control. Solution Fill an ASP.NET Image control from a database field by pointing the ImageUrl property | Team LiB Recipe 7.7 Displaying an Image from a Database in a Web Forms Control Problem You need to display an image from a database column in an ASP.NET control. Solution Fill an ASP.NET Image control from a database field by pointing the ImageUrl property of an Image control to a web page that retrieves the image from the database. The solution contains three files the Web Forms page to display the image its code-behind file and the code-behind page that serves the image. The Web Forms page sample code displays the employee image in the Image control employeelmage. The code for the Web Forms page is shown in Example 7-13. Example 7-13. File ADOCookbookCS0707.aspx asp Image id employeeImage style Z-INDEX 102 LEFT 16px POSITION absolute TOP 56px runat server asp Image The code-behind used with the Web Forms page contains one event handler Form.Load Sets the ImageUrl property of the employeeImage Image control to the web page that serves the employee image then a parameter passed in the URL indicates the employee ID to retrieve. The C code for the code-behind is shown in Example 7-14. Example 7-14. File ADOCookbookCS0707.aspx.cs using System . . . private void Page_Load object sender System.EventArgs e Set the image URL to the page containing just the image. employeelmage.ImageUrl ADOCookbookCS0707b.aspx EmployeeId employeeIdTextBox.Text The code-behind that serves the image contains one event handler Form.Load Retrieves the image from the database for the specified employee ID. The image is served by setting the HTTP MIME type of the output stream to image bmp and writing the image to the stream. The C code for the code-behind is shown in Example 7-15. Example 7-15. File ADOCookbookCS0707b.aspx.cs Namespaces variables and constants using System using System.Configuration using System.Data using System.Data.SqlClient . . . private void Page_Load object sender System.EventArgs e Create the command to retrieve employee image specified. SqlConnection conn new .