GridView.AllowSorting 属性

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。

获取或设置一个值，该值指示是否启用排序功能。

public:
 virtual property bool AllowSorting { bool get(); void set(bool value); };

public virtual bool AllowSorting { get; set; }

member this.AllowSorting : bool with get, set

Public Overridable Property AllowSorting As Boolean

属性值

Boolean

如果启用排序功能，则为 true；否则为 false。默认值为 false。

示例

以下示例演示如何在使用自动生成的列时使用 AllowSorting 属性在控件中 GridView 启用排序。


<%@ 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>GridView AllowSorting Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>GridView AllowSorting Example</h3>

      <asp:gridview id="CustomersGridView" 
        datasourceid="CustomersSource" 
        autogeneratecolumns="true"
        emptydatatext="No data available." 
        allowsorting="true" 
        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="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">
<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>GridView AllowSorting Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>GridView AllowSorting Example</h3>

      <asp:gridview id="CustomersGridView" 
        datasourceid="CustomersSource" 
        autogeneratecolumns="true"
        emptydatatext="No data available." 
        allowsorting="true" 
        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="CustomersSource"
        selectcommand="Select [CustomerID], [CompanyName], [Address], [City], [PostalCode], [Country] From [Customers]"
        connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>" 
        runat="server"/>
        
    </form>
  </body>
</html>

以下示例演示如何在定义集合时Columns使用 AllowSorting 属性在控件中GridView启用排序。图像还会以编程方式添加到要排序的列的标题中，以指示排序方向。必须提供自己的图像才能使此示例正常工作。


<%@ 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_RowCreated(Object sender, GridViewRowEventArgs e)
  {
    
    // Use the RowType property to determine whether the 
    // row being created is the header row. 
    if (e.Row.RowType == DataControlRowType.Header)
    {
      // Call the GetSortColumnIndex helper method to determine
      // the index of the column being sorted.
      int sortColumnIndex = GetSortColumnIndex();
      
      if (sortColumnIndex != -1)
      {
        // Call the AddSortImage helper method to add
        // a sort direction image to the appropriate
        // column header. 
        AddSortImage(sortColumnIndex, e.Row);
      }
    }
  }

  // This is a helper method used to determine the index of the
  // column being sorted. If no column is being sorted, -1 is returned.
  int GetSortColumnIndex()
  {

    // Iterate through the Columns collection to determine the index
    // of the column being sorted.
    foreach (DataControlField field in CustomersGridView.Columns)
    {
      if (field.SortExpression == CustomersGridView.SortExpression)
      {
        return CustomersGridView.Columns.IndexOf(field);
      }
    }

    return -1;
  }

  // This is a helper method used to add a sort direction
  // image to the header of the column being sorted.
  void AddSortImage(int columnIndex, GridViewRow headerRow)
  {
    
    // Create the sorting image based on the sort direction.
    Image sortImage = new Image();
    if (CustomersGridView.SortDirection == SortDirection.Ascending)
    {
      sortImage.ImageUrl = "~/Images/Ascending.jpg";
      sortImage.AlternateText = "Ascending Order";
    }
    else
    {
      sortImage.ImageUrl = "~/Images/Descending.jpg";
      sortImage.AlternateText = "Descending Order";
    }

    // Add the image to the appropriate header cell.
    headerRow.Cells[columnIndex].Controls.Add(sortImage);
    
  }
    
</script>

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

      <asp:gridview id="CustomersGridView" 
        datasourceid="CustomersSource" 
        autogeneratecolumns="false"
        emptydatatext="No data available." 
        allowsorting="true"
        onrowcreated="CustomersGridView_RowCreated"
        runat="server">
        
        <columns>
          <asp:boundfield datafield="CustomerID"
            headertext="Customer ID"
            headerstyle-wrap="false" 
            sortexpression="CustomerID"/>
          <asp:boundfield datafield="CompanyName"
            headertext="CompanyName"
            headerstyle-wrap="false"
            sortexpression="CompanyName"/>
          <asp:boundfield datafield="Address"
            headertext="Address"
            headerstyle-wrap="false"
            sortexpression="Address"/>
          <asp:boundfield datafield="City"
            headertext="City"
            headerstyle-wrap="false"
            sortexpression="City"/>
          <asp:boundfield datafield="PostalCode"
            headertext="Postal Code"
            headerstyle-wrap="false"
            sortexpression="PostalCode" />
          <asp:boundfield datafield="Country"
            headertext="Country"
            headerstyle-wrap="false"
            sortexpression="Country"/>         
        </columns>
                
      </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_RowCreated(ByVal sender As Object, ByVal e As GridViewRowEventArgs)
    
    ' Use the RowType property to determine whether the 
    ' row being created is the header row. 
    If e.Row.RowType = DataControlRowType.Header Then
    
      ' Call the GetSortColumnIndex helper method to determine
      ' the index of the column being sorted.
      Dim sortColumnIndex As Integer = GetSortColumnIndex()
      
      If sortColumnIndex <> -1 Then
      
        ' Call the AddSortImage helper method to add
        ' a sort direction image to the appropriate
        ' column header. 
        AddSortImage(sortColumnIndex, e.Row)
    
      End If
      
    End If
    
  End Sub

  ' This is a helper method used to determine the index of the
  ' column being sorted. If no column is being sorted, -1 is returned.
  Function GetSortColumnIndex() As Integer

    ' Iterate through the Columns collection to determine the index
    ' of the column being sorted.
    Dim field As DataControlField
    For Each field In CustomersGridView.Columns
    
      If field.SortExpression = CustomersGridView.SortExpression Then
      
        Return CustomersGridView.Columns.IndexOf(field)

      End If
      
    Next

    Return -1
      
  End Function

  ' This is a helper method used to add a sort direction
  ' image to the header of the column being sorted.
  Sub AddSortImage(ByVal columnIndex As Integer, ByVal row As GridViewRow)

    ' Create the sorting image based on the sort direction.
    Dim sortImage As New Image()
    If CustomersGridView.SortDirection = SortDirection.Ascending Then
    
      sortImage.ImageUrl = "~/Images/Ascending.jpg"
      sortImage.AlternateText = "Ascending Order"
    
    Else
    
      sortImage.ImageUrl = "~/Images/Descending.jpg"
      sortImage.AlternateText = "Descending Order"
    
    End If
    ' Add the image to the appropriate header cell.
    row.Cells(columnIndex).Controls.Add(sortImage)
    
  End Sub
    
</script>

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

      <asp:gridview id="CustomersGridView" 
        datasourceid="CustomersSource" 
        autogeneratecolumns="false"
        emptydatatext="No data available." 
        allowsorting="true"
        onrowcreated="CustomersGridView_RowCreated"
        runat="server">
        
        <columns>
          <asp:boundfield datafield="CustomerID"
            headertext="Customer ID"
            headerstyle-wrap="false" 
            sortexpression="CustomerID"/>
          <asp:boundfield datafield="CompanyName"
            headertext="CompanyName"
            headerstyle-wrap="false"
            sortexpression="CompanyName"/>
          <asp:boundfield datafield="Address"
            headertext="Address"
            headerstyle-wrap="false"
            sortexpression="Address"/>
          <asp:boundfield datafield="City"
            headertext="City"
            headerstyle-wrap="false"
            sortexpression="City"/>
          <asp:boundfield datafield="PostalCode"
            headertext="Postal Code"
            headerstyle-wrap="false"
            sortexpression="PostalCode" />
          <asp:boundfield datafield="Country"
            headertext="Country"
            headerstyle-wrap="false"
            sortexpression="Country"/>         
        </columns>
                
      </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>

注解

当支持排序的数据源控件绑定到控件 GridView 时，该 GridView 控件可以利用数据源控件的功能并提供自动排序功能。当 GridView 控件通过编程方式设置 DataSource 属性绑定到数据源时，必须使用事件提供排序功能 Sorting 。

备注

不同的数据源对启用其排序功能有不同的要求。若要确定要求，请参阅特定数据源的文档。

若要启用排序，请将 AllowSorting 属性设置为 true。启用排序后，其属性集的每个列字段 SortExpression 的标题文本将显示为链接按钮。

备注

SortExpression自动生成的列字段的属性会自动填充。如果通过 Columns 集合定义自己的列，则必须为每个列设置 SortExpression 属性;否则，列将不会在标题中显示链接按钮。

单击列的链接按钮会根据排序表达式对 GridView 控件中的项进行排序。通常，排序表达式只是列中显示的字段的名称，这会导致 GridView 控件针对该列进行排序。若要按多个字段排序，请使用包含以逗号分隔的字段名称列表的排序表达式。可以使用属性确定控件正在SortExpression应用的排序表达式GridView。单击列的链接按钮会重复切换升序和降序之间的排序方向。若要确定当前排序方向，请使用 SortDirection 属性。

控件 GridView 提供了多个事件，可用于在排序发生时执行自定义操作。下表列出了可用的事件。

事件	说明
Sorted	在单击用于列排序的超链接时，但在 GridView 控件对相应的排序操作进行处理之后发生。此事件通常用于在用户单击超链接对列进行排序后执行任务。
Sorting	在单击用于列排序的超链接时，但在 GridView 控件对相应的排序操作进行处理之前发生。此事件通常用于取消排序操作或执行自定义排序例程。

适用于

通过

GridView.AllowSorting 属性

定义

属性值

示例

注解

适用于

另请参阅

其他资源