Can't Show image in gridview using templates
- by n10i
i am trying to load images from the northwind database (categories table, images that are stored in the database) into grid view control. But it dosenot seems to work. Plz! have a look...
Default.aspx
<asp:GridView ID="GridView1" runat="server" AllowSorting="True"
AutoGenerateColumns="False" DataKeyNames="CategoryID"
DataSourceID="NorthWindSQLExpressConnectionString"
EnableModelValidation="True">
<Columns>
<asp:BoundField DataField="CategoryID" HeaderText="CategoryID"
InsertVisible="False" ReadOnly="True" SortExpression="CategoryID" />
<asp:BoundField DataField="CategoryName" HeaderText="CategoryName"
SortExpression="CategoryName" />
<asp:BoundField DataField="Description" HeaderText="Description"
SortExpression="Description" />
<asp:TemplateField HeaderText="Picture" SortExpression="Picture">
<EditItemTemplate>
<asp:TextBox ID="TextBox1" runat="server" Text='<%# Bind("Picture") %>'></asp:TextBox>
</EditItemTemplate>
<ItemTemplate>
<asp:Image ID="Image1" runat="server" ImageUrl='<%# RetriveImage(Eval("CategoryID")) %>' />
</ItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>
<asp:SqlDataSource ID="NorthWindSQLExpressConnectionString" runat="server"
ConnectionString="<%$ ConnectionStrings:NorthwindSQLExpressConnectionString %>"
SelectCommand="SELECT [CategoryID], [CategoryName], [Description], [Picture] FROM [Categories]">
</asp:SqlDataSource>
</div>
</form>
[Partial] Default.aspx.cs
protected string RetriveImage(object eval)
{
return ("ImageHandler.ashx?CategoryID=" + eval.ToString());
}
[Partial] ImageHandler.ashx
public void ProcessRequest(HttpContext context)
{
if (context.Request.QueryString == null)
{
}
else
{
try
{
using (var sqlCon = new SqlConnection(conString))
{
const string cmdString =
"Select picture from Categories where CategoryID=@CategoryID";
using (var sqlCmd = new SqlCommand(cmdString, sqlCon))
{
sqlCmd.Parameters.AddWithValue("@CategoryID", context.Request.QueryString["CategoryID"]);
string trmp = sqlCmd.ToString();
sqlCon.Open();
using (var sqlDr = sqlCmd.ExecuteReader())
{
sqlDr.Read();
context.Response.BinaryWrite((byte[])sqlDr["Picture"]);
}
}
}
}
catch (Exception ex)
{
context.Response.Write(ex.Message);
}
}
}
