DetailsViewModeEventHandler Delegera

Definition

Namnområde:: System.Web.UI.WebControls

Sammansättning:: System.Web.dll

Viktigt

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Representerar den metod som hanterar händelsen för ModeChanging en DetailsView kontroll.

public delegate void DetailsViewModeEventHandler(System::Object ^ sender, DetailsViewModeEventArgs ^ e);

public delegate void DetailsViewModeEventHandler(object sender, DetailsViewModeEventArgs e);

type DetailsViewModeEventHandler = delegate of obj * DetailsViewModeEventArgs -> unit

Public Delegate Sub DetailsViewModeEventHandler(sender As Object, e As DetailsViewModeEventArgs)

Parametrar

sender: Object

Källan till händelsen.

e: DetailsViewModeEventArgs

En DetailsViewModeEventArgs som innehåller händelsedata.

Exempel

I följande kodexempel visas hur du programmatiskt lägger till ett DetailsViewModeEventHandler ombud till ModeChanging händelsen för en DetailsView kontroll.


<%@ 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 Page_Load(Object sender, EventArgs e)
  {

    // Create a new DetailsView object.
    DetailsView customerDetailsView = new DetailsView();

    // Set the DetailsView object's properties.
    customerDetailsView.ID = "CustomerDetailsView";
    customerDetailsView.DataSourceID = "DetailsViewSource";
    customerDetailsView.AutoGenerateRows = true;
    customerDetailsView.AutoGenerateEditButton = true;
    customerDetailsView.AllowPaging = true;
    customerDetailsView.DataKeyNames = new String[1] { "CustomerID" };

    // Programmatically register the event-handling method
    // for the ItemInserted event of a DetailsView control.
    customerDetailsView.ModeChanging += new DetailsViewModeEventHandler(this.CustomerDetailsView_ModeChanging);

    // Add the DetailsView object to the Controls collection
    // of the PlaceHolder control.
    DetailsViewPlaceHolder.Controls.Add(customerDetailsView);

  }
  
  void CustomerDetailsView_ModeChanging(Object sender, DetailsViewModeEventArgs e)
  {

    // Use the sender parameter to access the DetailsView
    // control that raised the event.
    DetailsView customerDetailsView = (DetailsView)sender;

    // Use the NewMode property to determine the mode to which the 
    // DetailsView control is transitioning.
    switch (e.NewMode)
    {
      case DetailsViewMode.Edit:
        // Hide the pager row and clear the Label control
        // when transitioning to edit mode.
        customerDetailsView.AllowPaging = false;
        MessageLabel.Text = "";
        break;
      case DetailsViewMode.ReadOnly:
        // Display the pager row and confirmation message
        // when transitioning to edit mode.
        customerDetailsView.AllowPaging = true;
        if (e.CancelingEdit)
        {
          MessageLabel.Text = "Update canceled.";
        }
        else
        {
          MessageLabel.Text = "Update completed.";
        }
        break;
      case DetailsViewMode.Insert:
        // Cancel the mode change if the DetailsView
        // control attempts to transition to insert 
        // mode.
        e.Cancel = true;
        break;
      default:
        MessageLabel.Text = "Unsupported mode.";
        break;
    }
    
  }

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>DetailsViewModeEventHandler Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>DetailsViewModeEventHandler Example</h3>
      
      <!-- Use a PlaceHolder control as the container for the -->
      <!-- dynamically generated DetailsView control.         -->       
      <asp:PlaceHolder id="DetailsViewPlaceHolder"
        runat="server"/>
        
      <br/><br/>
      
      <asp:label id="MessageLabel"
        forecolor="Red"
        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="DetailsViewSource"
        selectcommand="Select [CustomerID], [CompanyName], [Address], 
          [City], [PostalCode], [Country] From [Customers]"
        updatecommand="Update [Customers] Set 
          [CompanyName]=@CompanyName, [Address]=@Address, 
          [City]=@City, [PostalCode]=@PostalCode, 
          [Country]=@Country 
          Where [CustomerID]=@CustomerID" 
        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 Page_Load(ByVal sender As Object, ByVal e As EventArgs)

    ' Create a new DetailsView object.
    Dim customerDetailsView As New DetailsView()

    ' Set the DetailsView object's properties.
    customerDetailsView.ID = "CustomerDetailsView"
    customerDetailsView.DataSourceID = "DetailsViewSource"
    customerDetailsView.AutoGenerateRows = True
    customerDetailsView.AutoGenerateEditButton = True
    customerDetailsView.AllowPaging = True
    
    Dim keyArray() As String = {"CustomerID"}
    customerDetailsView.DataKeyNames = keyArray
    
    ' Programmatically register the event-handling method
    ' for the ItemInserted event of a DetailsView control.
    AddHandler customerDetailsView.ModeChanging, AddressOf CustomerDetailsView_ModeChanging

    ' Add the DetailsView object to the Controls collection
    ' of the PlaceHolder control.
    DetailsViewPlaceHolder.Controls.Add(customerDetailsView)

  End Sub
  
  Sub CustomerDetailsView_ModeChanging(ByVal sender As Object, ByVal e As DetailsViewModeEventArgs)

    ' Use the sender parameter to access the DetailsView
    ' control that raised the event.
    Dim customerDetailsView As DetailsView = CType(sender, DetailsView)

    ' Use the NewMode property to determine the mode to which the 
    ' DetailsView control is transitioning.
    Select Case e.NewMode
    
      Case DetailsViewMode.Edit
        ' Hide the pager row and clear the Label control
        ' when transitioning to edit mode.
        customerDetailsView.AllowPaging = False
        MessageLabel.Text = ""

      Case DetailsViewMode.ReadOnly
        ' Display the pager row and confirmation message
        ' when transitioning to edit mode.
        customerDetailsView.AllowPaging = True
        If e.CancelingEdit Then
        
          MessageLabel.Text = "Update canceled."
        
        Else
        
          MessageLabel.Text = "Update completed."
        
        End If

      Case DetailsViewMode.Insert
        ' Cancel the mode change if the DetailsView
        ' control attempts to transition to insert 
        ' mode.
        e.Cancel = True

      Case Else
        MessageLabel.Text = "Unsupported mode."
          
    End Select
    
  End Sub

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>DetailsViewModeEventHandler Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>DetailsViewModeEventHandler Example</h3>
      
      <!-- Use a PlaceHolder control as the container for the -->
      <!-- dynamically generated DetailsView control.         -->       
      <asp:PlaceHolder id="DetailsViewPlaceHolder"
        runat="server"/>
        
      <br/><br/>
      
      <asp:label id="MessageLabel"
        forecolor="Red"
        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="DetailsViewSource"
        selectcommand="Select [CustomerID], [CompanyName], [Address], 
          [City], [PostalCode], [Country] From [Customers]"
        updatecommand="Update [Customers] Set 
          [CompanyName]=@CompanyName, [Address]=@Address, 
          [City]=@City, [PostalCode]=@PostalCode, 
          [Country]=@Country 
          Where [CustomerID]=@CustomerID" 
        connectionstring=
          "<%$ ConnectionStrings:NorthWindConnectionString%>" 
        runat="server"/>
            
    </form>
  </body>
</html>

Följande kodexempel visar hur du deklarativt lägger till ett DetailsViewModeEventHandler ombud i ModeChanging händelsen för en DetailsView kontroll.


<%@ 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 CustomerDetailsView_ModeChanging(Object sender, DetailsViewModeEventArgs e)
  {

    // Use the NewMode property to determine the mode to which the 
    // DetailsView control is transitioning.
    switch (e.NewMode)
    {
      case DetailsViewMode.Edit:
        // Hide the pager row and clear the Label control
        // when transitioning to edit mode.
        CustomerDetailsView.AllowPaging = false;
        MessageLabel.Text = "";
        break;
      case DetailsViewMode.ReadOnly:
        // Display the pager row and confirmation message
        // when transitioning to edit mode.
        CustomerDetailsView.AllowPaging = true;
        if (e.CancelingEdit)
        {
          MessageLabel.Text = "Update canceled.";
        }
        else
        {
          MessageLabel.Text = "Update completed.";
        }
        break;
      case DetailsViewMode.Insert:
        // Cancel the mode change if the DetailsView
        // control attempts to transition to insert 
        // mode.
        e.Cancel = true;
        break;
      default:
        MessageLabel.Text = "Unsupported mode.";
        break;
    }
    
  }

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>DetailsViewModeEventHandler Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>DetailsViewModeEventHandler Example</h3>
                
      <asp:detailsview id="CustomerDetailsView"
        datasourceid="DetailsViewSource"
        datakeynames="CustomerID"
        autogeneraterows="true"
        autogenerateeditbutton="true" 
        allowpaging="true"
        onmodechanging="CustomerDetailsView_ModeChanging" 
        runat="server">

      </asp:detailsview>
      
      <br/><br/>
      
      <asp:label id="MessageLabel"
        forecolor="Red"
        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="DetailsViewSource"
        selectcommand="Select [CustomerID], [CompanyName], [Address], 
          [City], [PostalCode], [Country] From [Customers]"
        updatecommand="Update [Customers] Set 
          [CompanyName]=@CompanyName, [Address]=@Address, 
          [City]=@City, [PostalCode]=@PostalCode, 
          [Country]=@Country 
          Where [CustomerID]=@CustomerID" 
        connectionstring=
          "<%$ ConnectionStrings:NorthWindConnectionString%>" 
        runat="server"/>
            
    </form>
  </body>
</html>


<%@ Page language="VB" autoeventwireup="false" %>

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

  Sub CustomerDetailsView_ModeChanging(ByVal sender As Object, ByVal e As DetailsViewModeEventArgs) Handles CustomerDetailsView.ModeChanging

    ' Use the NewMode property to determine the mode to which the 
    ' DetailsView control is transitioning.
    Select Case e.NewMode
    
      Case DetailsViewMode.Edit
        ' Hide the pager row and clear the Label control
        ' when transitioning to edit mode.
        CustomerDetailsView.AllowPaging = False
        MessageLabel.Text = ""

      Case DetailsViewMode.ReadOnly
        ' Display the pager row and confirmation message
        ' when transitioning to edit mode.
        CustomerDetailsView.AllowPaging = True
        If e.CancelingEdit Then
        
          MessageLabel.Text = "Update canceled."
        
        Else
        
          MessageLabel.Text = "Update completed."
        
        End If

      Case DetailsViewMode.Insert
        ' Cancel the mode change if the DetailsView
        ' control attempts to transition to insert 
        ' mode.
        e.Cancel = True

      Case Else
        MessageLabel.Text = "Unsupported mode."
          
    End Select
    
  End Sub

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>DetailsViewModeEventHandler Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>DetailsViewModeEventHandler Example</h3>
                
      <asp:detailsview id="CustomerDetailsView"
        datasourceid="DetailsViewSource"
        datakeynames="CustomerID"
        autogeneraterows="true"
        autogenerateeditbutton="true" 
        allowpaging="true"
        runat="server">

      </asp:detailsview>
      
      <br/><br/>
      
      <asp:label id="MessageLabel"
        forecolor="Red"
        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="DetailsViewSource"
        selectcommand="Select [CustomerID], [CompanyName], [Address], 
          [City], [PostalCode], [Country] From [Customers]"
        updatecommand="Update [Customers] Set 
          [CompanyName]=@CompanyName, [Address]=@Address, 
          [City]=@City, [PostalCode]=@PostalCode, 
          [Country]=@Country 
          Where [CustomerID]=@CustomerID" 
        connectionstring=
          "<%$ ConnectionStrings:NorthWindConnectionString%>" 
        runat="server"/>
            
    </form>
  </body>
</html>

Kommentarer

Händelsen ModeChanging utlöses när en DetailsView kontroll försöker ändra mellan redigering, infogning och skrivskyddat läge, men innan läget faktiskt ändras. På så sätt kan du ange en händelsehanterare som utför en anpassad rutin, till exempel att konfigurera DetailsView kontrollen för ett visst läge eller avbryta lägesändringen när den här händelsen inträffar.

När du skapar ett DetailsViewModeEventHandler ombud identifierar du den metod som ska hantera händelsen. Om du vill associera händelsen med händelsehanteraren lägger du till en instans av ombudet till händelsen. Händelsehanteraren anropas när händelsen inträffar, såvida du inte tar bort ombudet. Mer information om ombud för händelsehanterare finns i Hantera och höja händelser.

Tilläggsmetoder

Name	Description
GetMethodInfo(Delegate)	Hämtar ett objekt som representerar den metod som representeras av det angivna ombudet.

Gäller för

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