DataGrid.BackImageUrl Property

Definition

Gets or sets the URL of an image to display in the background of the DataGrid control.

[System.ComponentModel.Bindable(true)]
public virtual string BackImageUrl { get; set; }
public virtual string BackImageUrl { get; set; }

Property Value

The URL of an image to display in the background of the DataGrid control. The default value is Empty.

Attributes

Examples

The following code example demonstrates how use the BackImageUrl property to specify a background image for the DataGrid control.

<%@ Page Language="C#" AutoEventWireup="True" %>
<%@ Import Namespace="System.Data" %>
 
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
   <script language="C#" runat="server">
 
      ICollection CreateDataSource() 
      {
         DataTable dt = new DataTable();
         DataRow dr;
 
         dt.Columns.Add(new DataColumn("IntegerValue", typeof(Int32)));
         dt.Columns.Add(new DataColumn("StringValue", typeof(string)));
         dt.Columns.Add(new DataColumn("CurrencyValue", typeof(double)));
 
         for (int i = 0; i < 9; i++) 
         {
            dr = dt.NewRow();
 
            dr[0] = i;
            dr[1] = "Item " + i.ToString();
            dr[2] = 1.23 * (i + 1);
  
            dt.Rows.Add(dr);
         }
 
         DataView dv = new DataView(dt);
         return dv;
      }
 
      void Page_Load(Object sender, EventArgs e) 
      {
  
         if (!IsPostBack) 
         {
            // Need to load this data only once.
            ItemsGrid.DataSource= CreateDataSource();
            ItemsGrid.DataBind();
         }
      }
 
   </script>
 
<head runat="server">
    <title>DataGrid BackImageUrl Example</title>
</head>
<body>
 
   <form id="form1" runat="server">
 
      <h3>DataGrid BackImageUrl Example</h3>
 
      <b>Product List</b>
 
      <asp:DataGrid id="ItemsGrid"
           BorderColor="black"
           BorderWidth="1"
           CellPadding="3"
           AutoGenerateColumns="true"
           BackImageUrl="Images\image1.jpg"
           runat="server">

         <HeaderStyle BackColor="#00aaaa">
         </HeaderStyle>
 
      </asp:DataGrid>
 
   </form>
 
</body>
</html>

<%@ Page Language="C#" AutoEventWireup="True" %>
<%@ Import Namespace="System.Data" %>
 
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
   <script runat="server">
 
      ICollection CreateDataSource() 
      {
      
         // Create sample data for the DataGrid control.
         DataTable dt = new DataTable();
         DataRow dr;
 
         // Define the columns of the table.
         dt.Columns.Add(new DataColumn("IntegerValue", typeof(Int32)));
         dt.Columns.Add(new DataColumn("StringValue", typeof(string)));
         dt.Columns.Add(new DataColumn("CurrencyValue", typeof(double)));
         dt.Columns.Add(new DataColumn("BooleanValue", typeof(bool)));
 
         // Populate the table with sample values.
         for (int i = 0; i < 5; i++) 
         {
            dr = dt.NewRow();
 
            dr[0] = i;
            dr[1] = "Item " + i.ToString();
            dr[2] = 1.23 * (i + 1);
            dr[3] = false;
 
            dt.Rows.Add(dr);
         }

         // To persist the data source between posts to the server,
         // store it in session state.  
         Session["Source"] = dt;
 
         DataView dv = new DataView(dt);
         return dv;

      }
 
      void Page_Load(Object sender, EventArgs e) 
      {
 
         // Load sample data only once, when the page is first loaded.
         if (!IsPostBack) 
         {
            // Make sure to set the header text before binding the data to 
            // the DataGrid control; otherwise, the change will not appear 
            // until the next time the page is refreshed.
            ItemsGrid.Columns[0].HeaderText = "Item";

            ItemsGrid.DataSource = CreateDataSource();
            ItemsGrid.DataBind();
         }

      }

      void Button_Click(Object sender, EventArgs e) 
      {

         double subtotal = 0.0;

         // Update the data source with the user's selection and 
         // calculate the subtotal.
         DataTable dt = UpdateSource(ref subtotal);

         // Display the subtotal in the footer section of the third column.
         ItemsGrid.Columns[2].FooterText = 
             "Subtotal: " + subtotal.ToString("c");

         // Create a DataView and bind it to the DataGrid control.
         DataView dv = new DataView(dt);
         ItemsGrid.DataSource = dv;
         ItemsGrid.DataBind();

      }

      // This version of UpdateSource updates the data source and
      // calculates the subtotal.
      DataTable UpdateSource(ref double subtotal)
      {

         // Retrieve the data table from session state.
         DataTable dt = (DataTable)Session["Source"];

         // Iterate through the Items collection and update the data source
         // with the user's  selections. If an item is selected, add the
         // amount of the item to the subtotal.
         foreach (DataGridItem item in ItemsGrid.Items)
         {

            // Retrieve the SelectCheckBox CheckBox control from the  
            // specified item (row) in the DataGrid control.
            CheckBox selection = 
                (CheckBox)item.FindControl("SelectCheckBox");

            if (selection != null)
            {

               // Update the BooleanValue field with the value of 
               // the check box.
               dt.Rows[item.ItemIndex][3] = selection.Checked;

               // Add the value of the item to the subtotal if the item
               // is selected.
               if (selection.Checked)
               {
                  subtotal += 
                      Convert.ToDouble(item.Cells[2].Text.Substring(1));
               }

            }

         }

         // Save the data source.
         Session["Source"] = dt;

         return dt;

      }

      // This version of UpdateSource updates the data source only.
      DataTable UpdateSource()
      {

         // Retrieve the data table from session state.
         DataTable dt = (DataTable)Session["Source"];

         // Iterate through the Items collection and update the data source
         // with the user's  selections. If an item is selected, add the
         // amount of the item to the subtotal.
         foreach (DataGridItem item in ItemsGrid.Items)
         {

            // Retrieve the SelectCheckBox CheckBox control from the  
            // specified item (row) in the DataGrid control.
            CheckBox selection = 
                (CheckBox)item.FindControl("SelectCheckBox");

            if (selection != null)
            {

               // Update the BooleanValue field with the value of 
               // the check box.
               dt.Rows[item.ItemIndex][3] = selection.Checked;

            }

         }

         // Save the data source.
         Session["Source"] = dt;

         return dt;

      }

      void Selection_Change(Object sender, EventArgs e)
      {

         // Set the image for the header section of the first column in
         // the DataGrid control.
         ItemsGrid.BackImageUrl = List.SelectedItem.Value;

         // Create a DataView and bind it to the DataGrid control. This
         // will refresh the DataGrid control with the updated header image.
         DataView dv = new DataView(UpdateSource());
         ItemsGrid.DataSource = dv;
         ItemsGrid.DataBind();

      }

   </script>
 
<head runat="server">
    <title>DataGrid BackImageUrl Example</title>
</head>
<body>
 
   <form id="form1" runat="server">
 
      <h3>DataGrid BackImageUrl Example</h3>

      Select a background image for the DataGrid control.

      <br /><br />
 
      <b>Product List</b>
 
      <asp:DataGrid id="ItemsGrid"
           BorderColor="black"
           BorderWidth="1"
           CellPadding="3"
           ShowFooter="True"
           AutoGenerateColumns="False"
           BackImageUrl="image1.jpg"
           runat="server">

         <HeaderStyle BackColor="#00aaaa">
         </HeaderStyle>

         <FooterStyle BackColor="#00aaaa">
         </FooterStyle>

         <Columns>

            <asp:BoundColumn DataField="IntegerValue"/>

            <asp:BoundColumn DataField="StringValue"/>

            <asp:BoundColumn DataField="CurrencyValue" 
                 DataFormatString="{0:c}">

               <ItemStyle HorizontalAlign="Right">
               </ItemStyle>

            </asp:BoundColumn>

            <asp:TemplateColumn>

               <ItemTemplate>

                  <asp:CheckBox id="SelectCheckBox"
                       Text="Add to Cart"
                       Checked='<%# DataBinder.Eval(Container.DataItem, "BooleanValue") %>'
                       runat="server"/>

               </ItemTemplate>

            </asp:TemplateColumn>
 
         </Columns> 
 
      </asp:DataGrid>

      <br /><br />

      <asp:Button id="SubmitButton"
           Text="Submit"
           OnClick = "Button_Click"
           runat="server"/>
       
      <hr />

      Background image: <br /> 

      <asp:DropDownList id="List"
           AutoPostBack="True"
           OnSelectedIndexChanged="Selection_Change"
           runat="server">

         <asp:ListItem Selected="True" Value="image1.jpg"> Image 1 </asp:ListItem>
         <asp:ListItem Value="image2.jpg"> Image 2 </asp:ListItem>
         <asp:ListItem Value="image3.jpg"> Image 3 </asp:ListItem>
         <asp:ListItem Value="image4.jpg"> Image 4 </asp:ListItem>

      </asp:DropDownList>
 
   </form>
 
</body>
</html>

Remarks

Use the BackImageUrl property to specify an image to display in the background of the DataGrid control.

Note

If the specified image is smaller than the DataGrid control, the image will tile to fill in the background of the control.

Applies to

Product Versions
.NET Framework 1.1, 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1

See also