EditItemIndex Property

DataGrid.EditItemIndex Property

 

Gets or sets the index of an item in the DataGrid control to edit.

Namespace:   System.Web.UI.WebControls
Assembly:  System.Web (in System.Web.dll)

public virtual int EditItemIndex { get; set; }

Property Value

Type: System.Int32

The index of an item in the DataGrid control to edit. The default value is -1, which indicates that no item in the DataGrid control is being edited.

Exception Condition
ArgumentOutOfRangeException

The specified index is less than -1.

Use the EditItemIndex property when the DataGrid control contains an EditCommandColumn to determine the index of the item selected in the DataGrid control to edit.

This property is also used to programmatically control which item is being edited. Setting this property to an index of an item in the DataGrid control will enable editing controls for that item in the EditCommandColumn.

System_CAPS_noteNote

The EditItemIndex property is zero based.

To cancel editing, programmatically set this property to -1.

System_CAPS_cautionCaution

Text is not HTML encoded before it is displayed in the DataGrid control. This makes it possible to embed script within HTML tags in the text. If the values for the control come from user input, be sure to validate the values to reduce security vulnerabilities.

The following code example demonstrates how to use the EditItemIndex property to determine the item selected for editing in 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">

      DataTable Cart = new DataTable();
      DataView CartView;   

      void Page_Load(Object sender, EventArgs e) 
      {
         DataRow dr;

         if (Session["ShoppingCart"] == null) 
         {       

            Cart.Columns.Add(new DataColumn("Qty", typeof(String)));
            Cart.Columns.Add(new DataColumn("Item", typeof(String)));
            Cart.Columns.Add(new DataColumn("Price", typeof(String)));
            Session["ShoppingCart"] = Cart;

            // Create sample data.
            for (int i = 1; i <= 4; i++) 
            {
               dr = Cart.NewRow();
               if (i % 2 != 0)
                  dr[0] = "2";
               else
                  dr[0] = "1";
               dr[1] = "Item " + i.ToString();
               dr[2] = (1.23 * (i + 1)).ToString();
               Cart.Rows.Add(dr);
            }
         } 
         else
            Cart = (DataTable)Session["ShoppingCart"];          

         CartView = new DataView(Cart);
         CartView.Sort="Item";

         if (!IsPostBack)
            BindGrid(); 

      }

      void MyDataGrid_Edit(Object sender, DataGridCommandEventArgs e) 
      {
         MyDataGrid.EditItemIndex = e.Item.ItemIndex;
         BindGrid();
      }

      void MyDataGrid_Cancel(Object sender, DataGridCommandEventArgs e) 
      {
         MyDataGrid.EditItemIndex = -1;
         BindGrid();
      }

      void MyDataGrid_Update(Object sender, DataGridCommandEventArgs e) 
      {
         // For bound columns, the edited value is stored in a TextBox.
         // The TextBox is the 0th element in the column's cell.
         TextBox qtyText = (TextBox)e.Item.Cells[2].Controls[0];
         TextBox priceText = (TextBox)e.Item.Cells[3].Controls[0];

         String item = e.Item.Cells[1].Text;
         String qty = qtyText.Text;
         String price = priceText.Text;

         DataRow dr;

         // With a database, use an update command to update the data. Because 
         // the data source in this example is an in-memory DataTable, delete the 
         // old row and replace it with a new one.

         // Remove old entry.
         CartView.RowFilter = "Item='" + item + "'";
         if (CartView.Count > 0)
            CartView.Delete(0);
         CartView.RowFilter = "";

         // Add new entry.
         dr = Cart.NewRow();
         dr[0] = qty;
         dr[1] = item;
         dr[2] = price;
         Cart.Rows.Add(dr);

         MyDataGrid.EditItemIndex = -1;
         BindGrid();
      }

      void BindGrid() 
      {
         MyDataGrid.DataSource = CartView;
         MyDataGrid.DataBind();
      }

   </script>

<head runat="server">
    <title>DataGrid Editing Example</title>
</head>
<body style="font: 10pt verdana">

   <form id="form1" runat="server">

      <h3>DataGrid Editing Example</h3>

      <asp:DataGrid id="MyDataGrid" runat="server"
           BorderColor="black"
           BorderWidth="1"
           CellPadding="3"
           Font-Names="Verdana"
           Font-Size="8pt"
           OnEditCommand="MyDataGrid_Edit"
           OnCancelCommand="MyDataGrid_Cancel"
           OnUpdateCommand="MyDataGrid_Update"
           AutoGenerateColumns="false">

         <HeaderStyle BackColor="#aaaadd">
         </HeaderStyle>

         <Columns>

            <asp:EditCommandColumn
                 EditText="Edit"
                 CancelText="Cancel"
                 UpdateText="Update" 
                 HeaderText="Edit Command Column">

               <ItemStyle Wrap="false">
               </ItemStyle>

               <HeaderStyle Wrap="false">
               </HeaderStyle>

            </asp:EditCommandColumn>            

            <asp:BoundColumn HeaderText="Item" 
                 ReadOnly="true" 
                 DataField="Item"/>

            <asp:BoundColumn HeaderText="Quantity" 
                 DataField="Qty"/>

            <asp:BoundColumn HeaderText="Price" 
                 DataField="Price"/>

         </Columns>

      </asp:DataGrid>

   </form>

</body>
</html>

.NET Framework
Available since 1.1
Return to top
Show:
© 2016 Microsoft