FormViewCommandEventArgs 类

参考

定义

命名空间:: System.Web.UI.WebControls

程序集:: System.Web.dll

重要

一些信息与预发行产品相关，相应产品在发行之前可能会进行重大修改。对于此处提供的信息，Microsoft 不作任何明示或暗示的担保。

为 ItemCommand 事件提供数据。

public ref class FormViewCommandEventArgs : System::Web::UI::WebControls::CommandEventArgs

public class FormViewCommandEventArgs : System.Web.UI.WebControls.CommandEventArgs

type FormViewCommandEventArgs = class
    inherit CommandEventArgs

Public Class FormViewCommandEventArgs
Inherits CommandEventArgs

继承: Object

EventArgs

CommandEventArgs
FormViewCommandEventArgs

示例

以下示例演示如何使用 FormViewCommandEventArgs 传递给事件处理方法的对象来确定 ItemCommand 用户单击了控件中的 FormView 哪个按钮。

重要

此示例具有一个接受用户输入的文本框，这是一个潜在的安全威胁。默认情况下，ASP.NET 网页验证用户输入是否不包含脚本或 HTML 元素。有关详细信息，请参阅脚本侵入概述。


<%@ 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 ProductFormView_ItemCommand(Object sender, FormViewCommandEventArgs e)
  {

    // The ItemCommand event is raised when any button within
    // the FormView control is clicked. Use the CommandName property 
    // to determine which button was clicked. 
    if (e.CommandName == "Add")
    {

      // Add the product to the ListBox control. 
      
      // Use the Row property to retrieve the data row.
      FormViewRow row = ProductFormView.Row;
      
      // Retrieve the ProductNameLabel control from
      // the data row.
      Label productNameLabel = (Label)row.FindControl("ProductNameLabel");

      // Retrieve the QuantityTextBox control from
      // the data row.
      TextBox quantityTextBox = (TextBox)row.FindControl("QuantityTextBox");

      if (productNameLabel != null && quantityTextBox != null)
      {    
        // Get the product name from the ProductNameLabel control.
        string name = productNameLabel.Text;
        
        // Get the quantity from the QuantityTextBox control.
        string quantity = quantityTextBox.Text;

        // Create the text to display in the ListBox control.
        string description = name + " - " + quantity + " Qty";

        // Create a ListItem object using the description and
        // product name.
        ListItem item = new ListItem(description, name);

        // Add the ListItem object to the ListBox.
        ProductListBox.Items.Add(item);

        // Use the CommandSource property to retrieve
        // the Add button. Disable the button after
        // the user adds the currently displayed employee
        // name to the ListBox control.
        Button addButton = (Button)e.CommandSource;
        addButton.Enabled = false;
      }

    }

  }

  void ProductFormView_DataBound(Object sender, EventArgs e)
  {
    
    // To prevent the user from adding duplicate items, 
    // disable the Add button if the item being bound to the 
    // FormView control is already in the ListBox control.
    
    // Use the Row property to retrieve the data row.
    FormViewRow row = ProductFormView.Row;

    // Retrieve the Add button from the data row.
    Button addButton = (Button)row.FindControl("AddButton");

    // Retrieve the ProductNameLabel control from
    // data row.
    Label productNameLabel = (Label)row.FindControl("ProductNameLabel");

    if (addButton != null && productNameLabel != null)
    {
      // Get the product name from the ProductNameLabel 
      // control.
      string name = productNameLabel.Text;

      // Use the FindByValue method to determine whether
      // the ListBox control already contains an entry for
      // the item.
      ListItem item = ProductListBox.Items.FindByValue(name);

      // Disable the Add button if the ListBox control
      // already contains the item.
      if (item != null)
      {
        addButton.Enabled = false;
      }
      else
      {
        addButton.Enabled = true;
      }
    }

  }
    
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>FormViewCommandEventArgs Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>FormViewCommandEventArgs Example</h3>
                       
      <asp:formview id="ProductFormView"
        datasourceid="ProductSource"
        allowpaging="true"
        datakeynames="ProductID"
        onitemcommand="ProductFormView_ItemCommand"
        ondatabound="ProductFormView_DataBound"  
        runat="server">
        
        <itemtemplate>
        
          <table>
            <tr>
              <td style="width:400px">
                <b>Description:</b>
                <asp:label id="ProductNameLabel"
                  text='<%# Eval("ProductName") %>'
                  runat='server'/>
                <br/>      
                <b>Price:</b>
                <asp:label id="PriceLabel"
                  text='<%# Eval("UnitPrice", "{0:c}") %>'
                  runat='server'/>
                <br/>  
                <asp:textbox id="QuantityTextBox"
                  width="50px"
                  maxlength="3" 
                  runat="server"/> Qty                   
              </td>
            </tr>
            <tr>
              <td>
                <asp:requiredfieldvalidator ID="QuantityRequiredValidator"
                  controltovalidate="QuantityTextBox"
                  text="Please enter a quantity."
                  display="Static"
                  runat="server"/>
                <br/>
                <asp:CompareValidator id="QuantityCompareValidator"
                  controltovalidate="QuantityTextBox"
                  text="Please enter an integer value."
                  display="Static"
                  type="Integer"
                  operator="DataTypeCheck"  
                  runat="server"/>    
              </td>
            </tr>
            <tr>
              <td colspan="2">
                <asp:button id="AddButton"
                  text="Add"
                  commandname="Add"
                  runat="server"/>
              </td>
            </tr>
          </table>
        
        </itemtemplate>
                  
      </asp:formview>
      
      <br/><br/><hr/>
      
      Items:<br/>
      <asp:listbox id="ProductListBox"
        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="ProductSource"
        selectcommand="Select [ProductID], [ProductName], [UnitPrice] From [Products]"
        connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>" 
        runat="server"/>
            
    </form>
  </body>
</html>


<%@ Page language="VB" %>

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

  Sub ProductFormView_ItemCommand(ByVal sender As Object, ByVal e As FormViewCommandEventArgs)

    ' The ItemCommand event is raised when any button within
    ' the FormView control is clicked. Use the CommandName property 
    ' to determine which button was clicked. 
    If e.CommandName = "Add" Then

      ' Add the product to the ListBox control. 
      
      ' Use the Row property to retrieve the data row.
      Dim row As FormViewRow = ProductFormView.Row
      
      ' Retrieve the ProductNameLabel control from
      ' the data row.
      Dim productNameLabel As Label = CType(row.FindControl("ProductNameLabel"), Label)

      ' Retrieve the QuantityTextBox control from
      ' the data row.
      Dim quantityTextBox As TextBox = CType(row.FindControl("QuantityTextBox"), TextBox)

      If productNameLabel IsNot Nothing And quantityTextBox IsNot Nothing Then
          
        ' Get the product name from the ProductNameLabel control.
        Dim name As String = productNameLabel.Text
        
        ' Get the quantity from the QuantityTextBox control.
        Dim quantity As String = quantityTextBox.Text

        ' Create the text to display in the ListBox control.
        Dim description As String = name & " - " & quantity & " Qty"

        ' Create a ListItem object using the description and
        ' product name.
        Dim item As new ListItem(description, name)

        ' Add the ListItem object to the ListBox.
        ProductListBox.Items.Add(item)

        ' Use the CommandSource property to retrieve
        ' the Add button. Disable the button after
        ' the user adds the currently displayed employee
        ' name to the ListBox control.
        Dim addButton As Button = CType(e.CommandSource, Button)
        addButton.Enabled = False
        
      End If

    End If

  End Sub

  Sub ProductFormView_DataBound(ByVal sender As Object, ByVal e As EventArgs)
    
    ' To prevent the user from adding duplicate items, 
    ' disable the Add button if the item being bound to the 
    ' FormView control is already in the ListBox control.
    
    ' Use the Row property to retrieve the data row.
    Dim row As FormViewRow = ProductFormView.Row

    ' Retrieve the Add button from the data row.
    Dim addButton As Button = CType(row.FindControl("AddButton"), Button)

    ' Retrieve the ProductNameLabel control from
    ' data row.
    Dim productNameLabel As Label = CType(row.FindControl("ProductNameLabel"), Label)

    If addButton IsNot Nothing And productNameLabel IsNot Nothing Then
    
      ' Get the product name from the ProductNameLabel 
      ' control.
      Dim name As String = productNameLabel.Text

      ' Use the FindByValue method to determine whether
      ' the ListBox control already contains an entry for
      ' the item.
      Dim item As ListItem = ProductListBox.Items.FindByValue(name)

      ' Disable the Add button if the ListBox control
      ' already contains the item.
      If item IsNot Nothing Then
      
        addButton.Enabled = False
      
      Else
      
        addButton.Enabled = True
        
      End If
      
    End If

  End Sub
    
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>FormViewCommandEventArgs Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>FormViewCommandEventArgs Example</h3>
                       
      <asp:formview id="ProductFormView"
        datasourceid="ProductSource"
        allowpaging="true"
        datakeynames="ProductID"
        onitemcommand="ProductFormView_ItemCommand"
        ondatabound="ProductFormView_DataBound"  
        runat="server">
        
        <itemtemplate>
        
          <table>
            <tr>
              <td style="width:400px">
                <b>Description:</b>
                <asp:label id="ProductNameLabel"
                  text='<%# Eval("ProductName") %>'
                  runat='server'/>
                <br/>      
                <b>Price:</b>
                <asp:label id="PriceLabel"
                  text='<%# Eval("UnitPrice", "{0:c}") %>'
                  runat='server'/>
                <br/>  
                <asp:textbox id="QuantityTextBox"
                  width="50px"
                  maxlength="3" 
                  runat="server"/> Qty                   
              </td>
            </tr>
            <tr>
              <td>
                <asp:requiredfieldvalidator ID="QuantityRequiredValidator"
                  controltovalidate="QuantityTextBox"
                  text="Please enter a quantity."
                  display="Static"
                  runat="server"/>
                <br/>
                <asp:CompareValidator id="QuantityCompareValidator"
                  controltovalidate="QuantityTextBox"
                  text="Please enter an integer value."
                  display="Static"
                  type="Integer"
                  operator="DataTypeCheck"  
                  runat="server"/>    
              </td>
            </tr>
            <tr>
              <td colspan="2">
                <asp:button id="AddButton"
                  text="Add"
                  commandname="Add"
                  runat="server"/>
              </td>
            </tr>
          </table>
        
        </itemtemplate>
                  
      </asp:formview>
      
      <br/><br/><hr/>
      
      Items:<br/>
      <asp:listbox id="ProductListBox"
        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="ProductSource"
        selectcommand="Select [ProductID], [ProductName], [UnitPrice] From [Products]"
        connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>" 
        runat="server"/>
            
    </form>
  </body>
</html>

注解

单击 ItemCommand 控件中的按钮时， FormView 将引发事件。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。

控件中的 FormView 按钮还可以调用控件的某些内置功能。若要执行这些操作之一，请将按钮的属性设置为 CommandName 下表中的值之一。

CommandName 值	说明
“取消”	取消编辑或插入操作，并将 FormView 控件返回到由 DefaultMode 属性指定的模式。引发 ModeChanged 和 ModeChanging 事件。
“Delete”	删除当前记录。引发 ItemDeleted 和 ItemDeleting 事件。
“编辑”	将 FormView 控件置于编辑模式。引发 ModeChanged 和 ModeChanging 事件。
“Insert”	将当前记录插入到数据源中。引发 ItemInserted 和 ItemInserting 事件。
“新建”	将 FormView 控件置于插入模式。引发 ModeChanged 和 ModeChanging 事件。
“Page”	执行分页操作。将 `CommandArgument` 按钮的属性设置为“First”、“Last”、“Next”、“Prev”或页码，以指定要执行的分页操作的类型。引发 PageIndexChanged 和 PageIndexChanging 事件。
“更新”	更新数据源中的当前记录。引发 ItemUpdated 和 ItemUpdating 事件。

ItemCommand虽然单击上表中列出的按钮时会引发事件，但建议使用表中列出的事件执行操作。

对象 FormViewCommandEventArgs 将传递给事件处理方法，这样就可以确定所单击按钮的命令名称和命令参数。若要确定命令名称和命令参数，请分别使用 CommandName 和 CommandArgument 属性。还可以使用 CommandSource 属性访问引发事件的按钮控件。

有关如何处理事件的详细信息，请参阅处理和引发事件。

有关 FormViewCommandEventArgs 类的实例的初始属性值列表，请参见 FormViewCommandEventArgs 构造函数。

构造函数

FormViewCommandEventArgs(Object, CommandEventArgs)

初始化 FormViewCommandEventArgs 类的新实例。

属性

CommandArgument	获取命令的参数。 (继承自 CommandEventArgs)
CommandName	获取命令的名称。 (继承自 CommandEventArgs)
CommandSource	获取引发事件的控件。
Handled	获取或设置指示控件是否已处理事件的值。

方法

Equals(Object)	确定指定对象是否等于当前对象。 (继承自 Object)
GetHashCode()	作为默认哈希函数。 (继承自 Object)
GetType()	获取当前实例的 Type。 (继承自 Object)
MemberwiseClone()	创建当前 Object 的浅表副本。 (继承自 Object)
ToString()	返回表示当前对象的字符串。 (继承自 Object)

适用于

通过

FormViewCommandEventArgs 类

定义

示例

注解

构造函数

属性

方法

适用于

另请参阅

其他资源