GridView.SelectedDataKey 属性

参考

定义

命名空间:: System.Web.UI.WebControls

程序集:: System.Web.dll

重要

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获取 DataKey 对象，该对象包含 GridView 控件中选中行的数据键值。

public:
 virtual property System::Web::UI::WebControls::DataKey ^ SelectedDataKey { System::Web::UI::WebControls::DataKey ^ get(); };

[System.ComponentModel.Browsable(false)]
public virtual System.Web.UI.WebControls.DataKey SelectedDataKey { get; }

[<System.ComponentModel.Browsable(false)>]
member this.SelectedDataKey : System.Web.UI.WebControls.DataKey

Public Overridable ReadOnly Property SelectedDataKey As DataKey

属性值

DataKey

DataKey 控件中选中行的 GridView。默认值为 null，指示当前未选择行。

属性: BrowsableAttribute

例外

InvalidOperationException

DataKeyNames 属性中未指定数据键。

示例

下面的示例演示如何使用 SelectedDataKey 属性来确定控件中 GridView 所选行的数据键值。


<%@ 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_SelectedIndexChanged(Object sender, EventArgs e)  
  {
        
    // Display the primary key value of the selected row.
    Message.Text = "The primary key value of the selected row is " +
      CustomersGridView.SelectedDataKey.Value.ToString() + ".";
    
  }

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>GridView SelectedDataKey Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>GridView SelectedDataKey Example</h3>
            
      <asp:label id="Message"
        forecolor="Red"
        runat="server"/>
                
      <br/><br/>

      <asp:gridview id="CustomersGridView" 
        datasourceid="CustomersSource" 
        allowpaging="true"
        autogeneratecolumns="true"
        autogenerateselectbutton="true"    
        datakeynames="CustomerID"
        onselectedindexchanged="CustomersGridView_SelectedIndexChanged"   
        runat="server">
                
        <selectedrowstyle backcolor="LightBlue"
          forecolor="DarkBlue"/> 
               
      </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="CustomersSource"
        selectcommand="Select [CustomerID], [CompanyName], [Address], [City], [PostalCode], [Country] From [Customers]"
        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 CustomersGridView_SelectedIndexChanged(ByVal sender As Object, ByVal e As EventArgs)
        
    ' Display the primary key value of the selected row.
    Message.Text = "The primary key value of the selected row is " & _
      CustomersGridView.SelectedDataKey.Value.ToString() & "."
    
  End Sub

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>GridView SelectedDataKey Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>GridView SelectedDataKey Example</h3>
            
      <asp:label id="Message"
        forecolor="Red"
        runat="server"/>
                
      <br/><br/>

      <asp:gridview id="CustomersGridView" 
        datasourceid="CustomersSource" 
        allowpaging="true"
        autogeneratecolumns="true"
        autogenerateselectbutton="true"    
        datakeynames="CustomerID"
        onselectedindexchanged="CustomersGridView_SelectedIndexChanged"   
        runat="server">
                
        <selectedrowstyle backcolor="LightBlue"
          forecolor="DarkBlue"/> 
               
      </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="CustomersSource"
        selectcommand="Select [CustomerID], [CompanyName], [Address], [City], [PostalCode], [Country] From [Customers]"
        connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>" 
        runat="server"/>
            
    </form>
  </body>
</html>

以下示例演示如何使用第二个键字段作为主/详细信息方案中的参数。 GridView控件用于显示 Northwind 数据库的 Order Details 表中的记录。在控件中选择 GridView 记录时，产品表中的产品详细信息将显示在控件中 DetailsView 。 ProductID 是控件中的 GridView 第二个键名称。若要访问第二个键，GridView1.SelectedDataKey[1] 的值用作PropertyName ControlParameter控件控件DetailsView的对象SqlDataSource。


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

<!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" >
<head runat="server">
  <title>Selecting Data Key Values</title>
</head>
<body>
  <form id="form1" runat="server">
  <div>
    <asp:SqlDataSource 
      ID="SqlDataSource1" 
      runat="server" 
      ConnectionString="<%$ ConnectionStrings:NorthWindConnectionString%>"
      ProviderName="System.Data.SqlClient" 
      SelectCommand="SELECT * FROM [Order Details]">
    </asp:SqlDataSource>

    <asp:SqlDataSource 
      ID="SqlDataSource2" 
      runat="server" 
      ConnectionString="<%$ ConnectionStrings:NorthWindConnectionString%>"
      ProviderName="System.Data.SqlClient" 
      SelectCommand="SELECT * FROM [Products]WHERE [ProductID] = @productid">
      <SelectParameters>
        <asp:ControlParameter 
          Name="productid" 
          ControlID="GridView1" 
          PropertyName="SelectedDataKey[1]" />
      </SelectParameters>
    </asp:SqlDataSource>
    
  </div>

  <asp:GridView 
    ID="GridView1" 
    runat="server" 
    AllowPaging="True" 
    AutoGenerateColumns="False"
    DataKeyNames="OrderID,ProductID" DataSourceID="SqlDataSource1">
    <Columns>
      <asp:CommandField ShowSelectButton="True" />
      <asp:BoundField DataField="OrderID" HeaderText="OrderID" ReadOnly="True"/>
      <asp:BoundField DataField="ProductID" HeaderText="ProductID" ReadOnly="True" />
      <asp:BoundField DataField="UnitPrice" HeaderText="UnitPrice" />
      <asp:BoundField DataField="Quantity" HeaderText="Quantity" />
      <asp:BoundField DataField="Discount" HeaderText="Discount" />
      </Columns>
    </asp:GridView>
    <br />
    <asp:DetailsView 
      ID="DetailsView1" 
      runat="server" 
      AutoGenerateRows="False" 
      DataKeyNames="ProductID"
      DataSourceID="SqlDataSource2" 
      Height="50px" Width="125px">
      <Fields>
        <asp:BoundField 
          DataField="ProductID" 
          HeaderText="ProductID" 
          InsertVisible="False"
          ReadOnly="True" />
        <asp:BoundField DataField="ProductName" HeaderText="ProductName"/>
        <asp:BoundField DataField="SupplierID" HeaderText="SupplierID"/>
        <asp:BoundField DataField="CategoryID" HeaderText="CategoryID" />
        <asp:BoundField DataField="QuantityPerUnit" HeaderText="QuantityPerUnit" />
        <asp:BoundField DataField="UnitPrice" HeaderText="UnitPrice" />
        <asp:BoundField DataField="UnitsInStock" HeaderText="UnitsInStock" />
        <asp:BoundField DataField="UnitsOnOrder" HeaderText="UnitsOnOrder" />
        <asp:BoundField DataField="ReorderLevel" HeaderText="ReorderLevel" />
        <asp:CheckBoxField DataField="Discontinued" HeaderText="Discontinued" />
      </Fields>
    </asp:DetailsView>
  </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">

<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
  <title>Selecting Data Key Values</title>
</head>
<body>
  <form id="form1" runat="server">
  <div>
    <asp:SqlDataSource 
      ID="SqlDataSource1" 
      runat="server" 
      ConnectionString="<%$ ConnectionStrings:NorthWindConnectionString%>"
      ProviderName="System.Data.SqlClient" 
      SelectCommand="SELECT * FROM [Order Details]">
    </asp:SqlDataSource>

    <asp:SqlDataSource 
      ID="SqlDataSource2" 
      runat="server" 
      ConnectionString="<%$ ConnectionStrings:NorthWindConnectionString%>"
      ProviderName="System.Data.SqlClient" 
      SelectCommand="SELECT * FROM [Products]WHERE [ProductID] = @productid">
      <SelectParameters>
        <asp:ControlParameter 
          Name="productid" 
          ControlID="GridView1" 
          PropertyName="SelectedDataKey[1]" />
      </SelectParameters>
    </asp:SqlDataSource>
    
  </div>

  <asp:GridView 
    ID="GridView1" 
    runat="server" 
    AllowPaging="True" 
    AutoGenerateColumns="False"
    DataKeyNames="OrderID,ProductID" DataSourceID="SqlDataSource1">
    <Columns>
      <asp:CommandField ShowSelectButton="True" />
      <asp:BoundField DataField="OrderID" HeaderText="OrderID" ReadOnly="True"/>
      <asp:BoundField DataField="ProductID" HeaderText="ProductID" ReadOnly="True" />
      <asp:BoundField DataField="UnitPrice" HeaderText="UnitPrice" />
      <asp:BoundField DataField="Quantity" HeaderText="Quantity" />
      <asp:BoundField DataField="Discount" HeaderText="Discount" />
      </Columns>
    </asp:GridView>
    <br />
    <asp:DetailsView 
      ID="DetailsView1" 
      runat="server" 
      AutoGenerateRows="False" 
      DataKeyNames="ProductID"
      DataSourceID="SqlDataSource2" 
      Height="50px" Width="125px">
      <Fields>
        <asp:BoundField 
          DataField="ProductID" 
          HeaderText="ProductID" 
          InsertVisible="False"
          ReadOnly="True" />
        <asp:BoundField DataField="ProductName" HeaderText="ProductName"/>
        <asp:BoundField DataField="SupplierID" HeaderText="SupplierID"/>
        <asp:BoundField DataField="CategoryID" HeaderText="CategoryID" />
        <asp:BoundField DataField="QuantityPerUnit" HeaderText="QuantityPerUnit" />
        <asp:BoundField DataField="UnitPrice" HeaderText="UnitPrice" />
        <asp:BoundField DataField="UnitsInStock" HeaderText="UnitsInStock" />
        <asp:BoundField DataField="UnitsOnOrder" HeaderText="UnitsOnOrder" />
        <asp:BoundField DataField="ReorderLevel" HeaderText="ReorderLevel" />
        <asp:CheckBoxField DataField="Discontinued" HeaderText="Discontinued" />
      </Fields>
    </asp:DetailsView>
  </form>
</body>
</html>

注解

DataKeyNames设置属性后，该GridView控件使用指定字段或字段的值自动为控件中的每个行创建一个DataKey对象。 DataKey然后将对象添加到控件的DataKeys集合中。通常，该 DataKeys 属性用于检索 DataKey 控件中特定数据行的对象 GridView 。但是，如果只需要检索 DataKey 当前所选行的对象，只需将 SelectedDataKey 属性用作快捷方式。

备注

这与从DataKeys集合中的属性指定的SelectedIndex索引处检索DataKey对象相同。还可以使用 SelectedValue 该属性直接检索当前所选行的数据键值。

如果要创建对象并想要访问第一个ControlParameter字段以外的键字段，请使用该对象的属性中的PropertyName索引SelectedDataKey属性ControlParameter。下面显示了一个示例。

适用于

通过

GridView.SelectedDataKey 属性

定义

属性值

例外

示例

注解

适用于

另请参阅

其他资源