利用datagrid编辑数据

<form runat="server">

  <ASP:DataGrid id="MyDataGrid" runat="server"
       CellPadding = "2"
       EditItemStyle-BackColor="yellow"
       DataKeyField="ISBN"//后面可以使用DataKeys集合的行索引来获取该行的ISBN栏的值
       OnEditCommand="DoItemEdit"//Edit事件处理
       OnUpdateCommand="DoItemUpdate"//Update事件
       OnCancelCommand="DoItemCancel"//Cancel事件
       AutoGenerateColumns="False">

    <Columns>

      <ASP:BoundColumn DataField="ISBN" HeaderText="ISBN" ReadOnly="True" />//isbn栏（显示文本）

      <ASP:TemplateColumn HeaderText="Title">//模版列
        <ItemTemplate>
          <ASP:Label Text='<%# DataBinder.Eval(Container.DataItem, "Title") %>' runat="server" />
        </ItemTemplate>
        <EditItemTemplate>//EditItemIndex指向行的栏将显示此模版
          <ASP:TextBox id="txtTitle" Size="60"
               Text='<%# DataBinder.Eval(Container.DataItem, "Title") %>' runat="server" />
        </EditItemTemplate>
      </ASP:TemplateColumn>

      <ASP:BoundColumn DataField="PublicationDate" HeaderText="Published" />//Published文本栏

      <ASP:EditCommandColumn
           EditText="Edit"
           CancelText="Cancel"
           UpdateText="Update" />//编辑栏（显示为链接形式）

    </Columns>

  </ASP:DataGrid>

</form>

脚本：
<script language="C#" runat="server">

 void Page_Load(Object sender, EventArgs e)
 {
  if (!Page.IsPostBack)
   BindDataGrid();  // create data set and bind to grid control
 }

 
 void DoItemEdit(Object objSource, DataGridCommandEventArgs objArgs)
 {
  lblSQL.Text = "";  // clear text from label that shows SQL statement

  // set the EditItemIndex property of the grid to this item's index
               //设置EditItemIndex属性为用户所电击的行标
  MyDataGrid.EditItemIndex = objArgs.Item.ItemIndex;
  BindDataGrid();  // bind the data and display it
 }

 void DoItemUpdate(Object objSource, DataGridCommandEventArgs objArgs)
 {
  // get a reference to the title and publication date text boxes
                //objArgs.Item为激发事件的控件所在行的引用，FindControl则寻找id为txtTitle的textbox
  TextBox objTitleCtrl = (TextBox)objArgs.Item.FindControl("txtTitle");
                   //取出激发事件的控件所在行第三个单元中第一个控件（因为该Published栏无ID
                   //故不能使用findcontrol方法来查找）
  TextBox objPubDateCtrl = (TextBox)objArgs.Item.Cells[2].Controls[0];

  // create a suitable SQL statement and execute it
  string strSQL = "UPDATE Booklist SET Title='" + objTitleCtrl.Text + "', "
     + "PublicationDate='" + objPubDateCtrl.Text + "' "
     + "WHERE ISBN='" + MyDataGrid.DataKeys[objArgs.Item.ItemIndex] + "'";
  ExecuteSQLStatement(strSQL);//数据库更新操作

  // set EditItemIndex property of grid to -1 to switch out of Edit mode
  MyDataGrid.EditItemIndex = -1;//设为初始值
  BindDataGrid();  // bind the data and display it
 }

 void DoItemCancel(Object objSource, DataGridCommandEventArgs objArgs)
 {
  // set EditItemIndex property of grid to -1 to switch out of Edit mode
  MyDataGrid.EditItemIndex = -1;
  BindDataGrid();  // bind the data and display it
 }

 void ExecuteSQLStatement(string strSQL)
 {
  // this is where the SQL statement would be executed against the
  // original data source. In this example, we're simply displaying
  // the statement in a Label on the page
  lblSQL.Text = "<b>The SQL statement that would be executed is:</b><br />" + strSQL;
 }

 void BindDataGrid()
 {
  // get connection string from ../global/connect-strings.ascx user control
  string strConnect = ctlConnectStrings.OLEDBConnectionString;

  // create a SQL statement to select some rows from the database
  string strSelect = "SELECT * FROM BookList WHERE ISBN LIKE '%18610025%'";

  // create a variable to hold an instance of a DataReader object
  OleDbDataReader objDataReader;

  try
  {
   // create a new Connection object using the connection string
   OleDbConnection objConnect = new OleDbConnection(strConnect);

   // open the connection to the database
   objConnect.Open();

   // create a new Command using the connection object and select statement
   OleDbCommand objCommand = new OleDbCommand(strSelect, objConnect);

   // execute the SQL statement against the command to get the DataReader
   objDataReader = objCommand.ExecuteReader();
  }
  catch (Exception objError)
  {
   // display error details
   outError.InnerHtml = "<b>* Error while accessing data</b>.<br />"
        + objError.Message + "<br />" + objError.Source + "<p />";
   return;  //  and stop execution
  }

  // set the DataSource property and bind the grid
  MyDataGrid.DataSource = objDataReader;
  MyDataGrid.DataBind();
 }

</script>
注：
TextBox objTitleCtrl = (TextBox)objArgs.Item.FindControl("txtTitle");
TextBox objPubDateCtrl = (TextBox)objArgs.Item.Cells[2].Controls[0];
这两条语句而言，后者最适用于当栏是普通的BoundColumn或是自动生成的情况（没有定义ID）--而不适用于利用模版创建的自定义栏（
这就是为什么对Title栏使用FindControl的原因（定义了ID））