GridView.SelectedValue 屬性

  • 參考

定義

命名空間:
System.Web.UI.WebControls
組件:
System.Web.dll

取得 GridView 控制項中已選取資料列的資料索引鍵值。

public:
 property System::Object ^ SelectedValue { System::Object ^ get(); };
[System.ComponentModel.Browsable(false)]
public object SelectedValue { get; }
[<System.ComponentModel.Browsable(false)>]
member this.SelectedValue : obj
Public ReadOnly Property SelectedValue As Object

屬性值

Object

GridView 控制項中已選取資料列的資料索引鍵值。

屬性
BrowsableAttribute

範例

下列範例示範如何使用 SelectedValue 屬性來判斷 控制項中 GridView 所選資料列的資料索引鍵值。


<%@ 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.SelectedValue.ToString() + ".";
    
  }

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>GridView SelectedValue Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>GridView SelectedValue 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.SelectedValue.ToString() & "."
    
  End Sub

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>GridView SelectedValue Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>GridView SelectedValue 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>

備註

DataKeyNames當屬性設定為以逗號分隔的功能變數名稱清單，代表資料來源的主鍵時， GridView 控制項會自動使用指定欄位或欄位的值，為控制項中的每個資料列建立 DataKey 物件。 然後，物件 DataKey 會加入至控制項的 DataKeys 集合。 一般而言， DataKeys 屬性是用來擷取 DataKey 控制項中特定資料列的物件 GridView 。 不過，如果您只需要擷取 DataKey 目前選取之資料列的物件，只要使用 SelectedDataKey 屬性做為快捷方式即可。 做為進一步的快捷方式，您可以使用 屬性，直接判斷所選取資料列 SelectedValue 第一個索引鍵欄位的資料索引鍵值。

如果您要建立 ControlParameter 物件，而且想要存取第一個欄位以外的索引鍵欄位，請使用 SelectedDataKey 屬性。 如需範例，請參閱 SelectedDataKey。

適用於

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