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Listing 9.28 - PhotoGallery.aspx

Illustrates how to execute the SqlDataSource Select command programmatically.

Listing 9.28 - PhotoGallery.aspx (C#)
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<%@ Page Language="C#" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head id="Head1" runat="server">
    <title>Photo Gallery</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
    
    <asp:DataList
        id="dlstImages"
        DataSourceID="srcImages"
        RepeatColumns="3"
        Runat="server">
        <ItemTemplate>
        <asp:Image ID="Image1"
            ImageUrl='<%# String.Format("DynamicImage.ashx?id={0}", Eval("Id")) %>'
            Width="250"
            Runat="server" />
        <br />
        <%# Eval("Description") %>
    </ItemTemplate>
    </asp:DataList>
         
    <hr />

    <asp:FormView
        id="frmImage"
        DataSourceID="srcImages"
        DefaultMode="Insert"
        Runat="server">
        <InsertItemTemplate>
        <asp:Label
            id="lblImage"
            Text="Upload Image:"
            AssociatedControlId="upImage"
            Runat="server" />
        <br />    
        <asp:FileUpload
            id="upImage"
            FileBytes='<%# Bind("Image") %>'
            Runat="server" />
        
        <br /><br />
        
        <asp:Label
            id="lblDescription"
            Text="Description:"
            AssociatedControlID="txtDescription"
            Runat="server" />
        <br />    
        <asp:TextBox
            id="txtDescription"
            Text='<%# Bind("Description") %>'
            TextMode="MultiLine"
            Columns="50"
            Rows="2"
            Runat="server" />    
        
        <br /><br />
        
        <asp:Button
            id="btnInsert"
            Text="Add Image"
            CommandName="Insert"
            Runat="server" />    
        </InsertItemTemplate>
    </asp:FormView>    
        
   
    
    <asp:SqlDataSource
        id="srcImages"
        SelectCommand="SELECT ID,Description FROM Images"
        InsertCommand="INSERT Images (Image,Description)
            VALUES (@Image,@Description)"
        ConnectionString="<%$ ConnectionStrings:Images %>"
        Runat="server" />
    
    
    </div>
    </form>
</body>
</html>

The following generic handler is used to display the images.

Listing 9.29 - DynamicImage.ashx (C#)
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<%@ WebHandler Language="C#" Class="DynamicImage" %>

using System.Data;
using System.Web;
using System.Web.Configuration;
using System.Web.UI;
using System.Web.UI.WebControls;

/// <summary>
/// Displays an image corresponding to the Id passed
/// in a query string field
/// </summary>
public class DynamicImage : IHttpHandler 
{
    
    public void ProcessRequest (HttpContext context) 
    {
        // Get the Id of the image to display
        string imageId = context.Request.QueryString["Id"];
        
        // Use SqlDataSource to grab image bytes
        SqlDataSource src = new SqlDataSource();
        src.ConnectionString = WebConfigurationManager.ConnectionStrings["Images"].ConnectionString;
        src.SelectCommand = "SELECT Image FROM Images WHERE Id=" + imageId;

        // Return a DataView
        
        DataView view = (DataView)src.Select(DataSourceSelectArguments.Empty);
        context.Response.BinaryWrite( (byte[])view[0]["Image"]);

        // Return a DataReader
        //src.DataSourceMode = SqlDataSourceMode.DataReader;
        //IDataReader reader = (IDataReader)src.Select(DataSourceSelectArguments.Empty);
        //reader.Read();
        //context.Response.BinaryWrite((byte[])reader["Image"]);
        //reader.Close();
        
    }
 
    public bool IsReusable 
    {
        get 
        {
            return false;
        }
    }

}