GridViewEditEventHandler 委托

定义

表示处理 RowEditing 控件的 GridView 事件的方法。

C#
public delegate void GridViewEditEventHandler(object sender, GridViewEditEventArgs e);

参数

sender
Object

事件源。

e
GridViewEditEventArgs

包含事件数据的 GridViewEditEventArgs 对象。

示例

以下示例演示如何以编程方式将委托添加到GridViewEditEventHandlerRowEditing控件的事件GridView

ASP.NET (C#)

<%@ Page language="C#" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">

  void Page_Load(Object sender, EventArgs e)
  {
        
    // Create a new GridView control.
    GridView customersGridView = new GridView();

    // Set the GridView control's properties.
    customersGridView.ID = "CustomersGridView";
    customersGridView.DataSourceID = "CustomersSqlDataSource";
    customersGridView.AutoGenerateColumns = true;
    customersGridView.AutoGenerateEditButton = true;
    customersGridView.AllowPaging = true;
    customersGridView.DataKeyNames = new String[] { "CustomerID" };
      
    // Programmatically register the event-handling method.
    customersGridView.RowEditing += new GridViewEditEventHandler(this.CustomersGridView_RowEditing);
        
    // Add the GridView control to the Controls collection
    // of the PlaceHolder control.
    GridViewPlaceHolder.Controls.Add(customersGridView);
        
  }

  void CustomersGridView_RowEditing(Object sender, GridViewEditEventArgs e)
  {

    // User the sender parameter to retrieve the GridView control
    // that raised the event.
    GridView customersGridView = (GridView)sender;
    
    // Get the country for the row being edited. For this example, the
    // country is contained in the seventh column (index 6). 
    String country = customersGridView.Rows[e.NewEditIndex].Cells[6].Text;

    // For this example, cancel the edit operation if the user attempts
    // to edit the record of a customer from the USA. 
    if (country == "USA")
    {
      // Cancel the edit operation.
      e.Cancel = true;
      Message.Text = "You cannot edit this record.";
    }
    else
    {
      Message.Text = "";
    }
    
  }
    
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>GridViewEditEventHandler Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>GridViewEditEventHandler Example</h3>
          
      <asp:label id="Message"
        forecolor="Red"
        runat="server"/>
                
      <br/>
            
      <asp:placeholder id="GridViewPlaceHolder"
        runat="server"/>
            
      <!-- This example uses Microsoft SQL Server and connects  -->
      <!-- to the Northwind sample database. Use an ASP.NET     -->
      <!-- expression to retrieve the connection string value   -->
      <!-- from the Web.config file.                            -->
      <asp:sqldatasource id="CustomersSqlDataSource"  
        selectcommand="Select [CustomerID], [CompanyName], [Address], [City], [PostalCode], [Country] From [Customers]"
        updatecommand="Update Customers SET CompanyName=@CompanyName, Address=@Address, City=@City, PostalCode=@PostalCode, Country=@Country WHERE (CustomerID = @CustomerID)"
        connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>"
        runat="server">
      </asp:sqldatasource>
            
    </form>
  </body>
</html>

以下示例演示如何以声明方式将委托添加到GridViewEditEventHandlerRowEditing控件的事件GridView

ASP.NET (C#)

<%@ Page language="C#" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">

  void CustomersGridView_RowEditing(Object sender, GridViewEditEventArgs e)
  {
    
    // Get the country for the row being edited. For this example, the
    // country is contained in the seventh column (index 6). 
    String country = CustomersGridView.Rows[e.NewEditIndex].Cells[6].Text;

    // For this example, cancel the edit operation if the user attempts
    // to edit the record of a customer from the Unites States. 
    if (country == "USA")
    {
      // Cancel the edit operation.
      e.Cancel = true;
      Message.Text = "You cannot edit this record.";
    }
    else
    {
      Message.Text = "";
    }
    
  }
    
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>GridView RowEditing Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>GridView RowEditing Example</h3>
          
      <asp:label id="Message"
        forecolor="Red"
        runat="server"/>
                
      <br/>
            
      <!-- The GridView control automatically sets the columns     -->
      <!-- specified in the datakeynames property as read-only.    -->
      <!-- No input controls are rendered for these columns in     -->
      <!-- edit mode.                                              -->
      <asp:gridview id="CustomersGridView" 
        datasourceid="CustomersSqlDataSource" 
        autogeneratecolumns="true"
        autogenerateeditbutton="true"
        allowpaging="true" 
        datakeynames="CustomerID"
        onrowediting="CustomersGridView_RowEditing"   
        runat="server">
      </asp:gridview>
            
      <!-- This example uses Microsoft SQL Server and connects  -->
      <!-- to the Northwind sample database. Use an ASP.NET     -->
      <!-- expression to retrieve the connection string value   -->
      <!-- from the Web.config file.                            -->
      <asp:sqldatasource id="CustomersSqlDataSource"  
        selectcommand="Select [CustomerID], [CompanyName], [Address], [City], [PostalCode], [Country] From [Customers]"
        updatecommand="Update Customers SET CompanyName=@CompanyName, Address=@Address, City=@City, PostalCode=@PostalCode, Country=@Country WHERE (CustomerID = @CustomerID)"
        connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>"
        runat="server">
      </asp:sqldatasource>
            
    </form>
  </body>
</html>

注解

RowEditing当“编辑”按钮 (按钮,其CommandName属性设置为“编辑”) 单击控件进入编辑模式之前GridView,将引发 该事件。 这允许你提供一个事件处理方法,该方法在发生此事件时执行自定义例程,例如取消编辑操作。

创建 GridViewEditEventHandler 委托时,需要标识将处理该事件的方法。 若要将事件与事件处理程序关联,请将该委托的一个实例添加到事件中。 除非移除了该委托,否则每当发生该事件时就会调用事件处理程序。 有关事件处理程序委托的详细信息,请参阅 处理和引发事件

扩展方法

GetMethodInfo(Delegate)

获取指示指定委托表示的方法的对象。

适用于

产品 版本
.NET Framework 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

另请参阅