ObjectDataSourceView.DeleteMethod 屬性

參考

定義

命名空間:: System.Web.UI.WebControls

組件:: System.Web.dll

重要

部分資訊涉及發行前產品，在發行之前可能會有大幅修改。 Microsoft 對此處提供的資訊，不做任何明確或隱含的瑕疵擔保。

取得或設定 ObjectDataSourceView 物件叫用 (Invoke) 以刪除資料之方法或函式的名稱。

public:
 property System::String ^ DeleteMethod { System::String ^ get(); void set(System::String ^ value); };

public string DeleteMethod { get; set; }

member this.DeleteMethod : string with get, set

Public Property DeleteMethod As String

屬性值

String

字串，表示 ObjectDataSourceView 用於刪除資料之方法或函式的名稱。預設為空字串 ("")。

範例

下列程式碼範例示範如何使用 ObjectDataSource 控制項搭配商務物件和 GridView 控制項來刪除資料。 GridView一開始會使用屬性所 SelectMethod 指定的方法來擷 EmployeeLogic 取物件中的資料，顯示一組所有員工。 AutoGenerateDeleteButton由於屬性設定為 true ，因此 GridView 控制項會自動顯示[刪除]按鈕。

如果您按一下 [ 刪除] 按鈕，則會 Delete 使用屬性所 DeleteMethod 指定的方法以及集合中指定的 DeleteParameters 任何參數來執行作業。在此程式碼範例中，也會執行一些前置處理和後置處理步驟。呼叫 NorthwindEmployeeDeleting 委派以在作業執行之前 Delete 處理 Deleting 事件，並 NorthwindEmployeeDeleted 呼叫委派以在作業完成之後 Delete 處理 Deleted 事件，以執行例外狀況處理。在此範例中，如果 NorthwindDataException 擲回，則會由這個委派處理。

若要檢查此程式碼範例所使用的仲介層商務物件的實 EmployeeLogic 作，請參閱 ObjectDataSourceStatusEventArgs 。

<%@ Register TagPrefix="aspSample" Namespace="Samples.AspNet.CS" Assembly="Samples.AspNet.CS" %>
<%@ Import namespace="Samples.AspNet.CS" %>
<%@ 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">
private void NorthwindEmployeeDeleting(object source, ObjectDataSourceMethodEventArgs e)
{
  // The GridView passes the ID of the employee
  // to be deleted. However, the buisiness object, EmployeeLogic,
  // requires a NorthwindEmployee parameter, named "ne". Create
  // it now and add it to the parameters collection.
  IDictionary paramsFromPage = e.InputParameters;
  if (paramsFromPage["EmpID"] != null) {
    NorthwindEmployee ne
      = new NorthwindEmployee( Int32.Parse(paramsFromPage["EmpID"].ToString()));
    // Remove the old EmpID parameter.
    paramsFromPage.Clear();
    paramsFromPage.Add("ne", ne);
  }
}

private void NorthwindEmployeeDeleted(object source, ObjectDataSourceStatusEventArgs e)
{
  // Handle the Exception if it is a NorthwindDataException
  if (e.Exception != null)
  {

    // Handle the specific exception type. The ObjectDataSource wraps
    // any Exceptions in a TargetInvokationException wrapper, so
    // check the InnerException property for expected Exception types.
    if (e.Exception.InnerException is NorthwindDataException)
    {
      Label1.Text = e.Exception.InnerException.Message;
      // Because the exception is handled, there is
      // no reason to throw it.
      e.ExceptionHandled = true;
    }
  }
}

</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
  <head>
    <title>ObjectDataSource - C# Example</title>
  </head>
  <body>
    <form id="Form1" method="post" runat="server">

        <asp:gridview
          id="GridView1"
          runat="server"
          datasourceid="ObjectDataSource1"
          autogeneratedeletebutton="true"
          autogeneratecolumns="false"
          datakeynames="EmpID">
          <columns>
            <asp:boundfield headertext="EmpID" datafield="EmpID" />
            <asp:boundfield headertext="First Name" datafield="FirstName" />
            <asp:boundfield headertext="Last Name" datafield="LastName" />
          </columns>
        </asp:gridview>

        <asp:objectdatasource
          id="ObjectDataSource1"
          runat="server"
          selectmethod="GetAllEmployees"
          deletemethod="DeleteEmployee"
          ondeleting="NorthwindEmployeeDeleting"
          ondeleted="NorthwindEmployeeDeleted"
          typename="Samples.AspNet.CS.EmployeeLogic">
          <deleteparameters>
            <asp:parameter name="EmpID" type="Int32" />
          </deleteparameters>
        </asp:objectdatasource>

        <asp:label id="Label1" runat="server" />

    </form>
  </body>
</html>

<%@ Register TagPrefix="aspSample" Namespace="Samples.AspNet.VB" Assembly="Samples.AspNet.VB" %>
<%@ Import namespace="Samples.AspNet.VB" %>
<%@ 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">
' Called before a Delete operation.
    Private Sub NorthwindEmployeeDeleting(ByVal source As Object, ByVal e As ObjectDataSourceMethodEventArgs)

        ' The GridView passes the ID of the employee
        ' to be deleted. However, the business object, EmployeeLogic,
        ' requires a NorthwindEmployee parameter, named "ne". Create
        ' it now and add it to the parameters collection.
        Dim paramsFromPage As IDictionary = e.InputParameters
  
        If Not paramsFromPage("EmpID") Is Nothing Then
    
            Dim ne As New NorthwindEmployee(paramsFromPage("EmpID").ToString())
            ' Remove the old EmpID parameter.
            paramsFromPage.Clear()
            paramsFromPage.Add("ne", ne)
    
    
        End If
    End Sub ' NorthwindEmployeeDeleting

    ' Called after a Delete operation.
    Private Sub NorthwindEmployeeDeleted(ByVal source As Object, ByVal e As ObjectDataSourceStatusEventArgs)
        ' Handle the Exception if it is a NorthwindDataException.
        If Not e.Exception Is Nothing Then

            ' Handle the specific exception type. The ObjectDataSource wraps
            ' any Exceptions in a TargetInvokationException wrapper, so
            ' check the InnerException property for the expected Exception types.
            If e.Exception.InnerException.GetType().Equals(GetType(NorthwindDataException)) Then

                Label1.Text = e.Exception.InnerException.Message
                ' Because the exception is handled, there is
                ' no reason to throw it.
                e.ExceptionHandled = True
      
            End If
        End If
    End Sub ' NorthwindEmployeeDeleted
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
  <head>
    <title>ObjectDataSource - VB Example</title>
  </head>
  <body>
    <form id="Form1" method="post" runat="server">

        <asp:gridview
          id="GridView1"
          runat="server"
          datasourceid="ObjectDataSource1"
          autogeneratedeletebutton="true"
          autogeneratecolumns="false"
          datakeynames="EmpID">
          <columns>
            <asp:boundfield headertext="EmpID" datafield="EmpID" />
            <asp:boundfield headertext="First Name" datafield="FirstName" />
            <asp:boundfield headertext="Last Name" datafield="LastName" />
          </columns>
        </asp:gridview>

        <asp:objectdatasource
          id="ObjectDataSource1"
          runat="server"
          selectmethod="GetAllEmployees"
          deletemethod="DeleteEmployee"
          ondeleting="NorthwindEmployeeDeleting"
          ondeleted="NorthwindEmployeeDeleted"
          typename="Samples.AspNet.VB.EmployeeLogic">
          <deleteparameters>
            <asp:parameter name="EmpID" type="Int32" />
          </deleteparameters>
        </asp:objectdatasource>

        <asp:label id="Label1" runat="server" />

    </form>
  </body>
</html>

備註

屬性所 DeleteMethod 識別的方法可以是 Visual Basic) 方法中的實例方法或 static (Shared 。如果是實例方法，則每次呼叫屬性所 DeleteMethod 指定的方法時，都會建立和終結商務物件。您可以處理 ObjectCreated 事件，以在呼叫屬性所 DeleteMethod 指定的方法之前，使用商務物件。您也可以處理 ObjectDisposing 呼叫屬性所 DeleteMethod 指定方法之後所引發的事件。如果方法是 static Visual Basic) 方法中的 (Shared ，則永遠不會建立商務物件，而且您無法處理這些事件。

如果控制項使用的商務物件 ObjectDataSource 會實作多個具有相同名稱的方法或函式， (方法多載) ，資料來源控制項會嘗試根據一組條件叫用正確的方法，包括集合中的 DeleteParameters 參數。如果集合中的 DeleteParameters 參數不符合方法簽章的參數 DeleteMethod ，資料來源會擲回例外狀況。

屬性的值 DeleteMethod 會儲存在檢視狀態中。

如需詳細資訊，請參閱DeleteMethod。

適用於

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ObjectDataSourceView.DeleteMethod 屬性

定義

屬性值

範例

備註

適用於

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