WebPartZoneBase.OnCreateVerbs Method (WebPartVerbsEventArgs)

 
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Raises the CreateVerbs event.

Namespace:   System.Web.UI.WebControls.WebParts
Assembly:  System.Web (in System.Web.dll)

Protected Overridable Sub OnCreateVerbs (
	e As WebPartVerbsEventArgs
)

Parameters

e
Type: System.Web.UI.WebControls.WebParts.WebPartVerbsEventArgs

An EventArgs that contains the event data.

You can override the OnCreateVerbs method in a derived WebPartZoneBase zone class to add additional WebPartVerb objects to the collection of standard verbs in your zone. You can do this by adding verbs to the collection in the Verbs property.

The following code example demonstrates a way to create a handler for the CreateVerbs event by overriding the OnCreateVerbs method to add a custom verb to a derived WebPartZoneBase zone.

The code example contains two source files. For the code example to run, you must compile this source code. You can compile it explicitly and put the resulting assembly in your Web site's Bin folder or the global assembly cache. Alternatively, you can put the source code in your site's App_Code folder, where it will be dynamically compiled at run time. This code example uses dynamic compilation. For a walkthrough that demonstrates how to compile, see Walkthrough: Developing and Using a Custom Web Server Control.

The first part of the code example is the source code for a simple control derived from the WebPart class.

Imports System
Imports System.Data
Imports System.Configuration
Imports System.Web
Imports System.Web.Security
Imports System.Collections.Generic
Imports System.Security.Permissions
Imports System.Web.UI
Imports System.Web.UI.WebControls
Imports System.Web.UI.WebControls.WebParts
Imports System.Web.UI.HtmlControls

' This code snippet creates a simple Web Part control.
Namespace Samples.AspNet.VB.Controls

  <AspNetHostingPermission(SecurityAction.Demand, _
    Level:=AspNetHostingPermissionLevel.Minimal)> _
  <AspNetHostingPermission(SecurityAction.InheritanceDemand, _
    Level:=AspNetHostingPermissionLevel.Minimal)> _
  Public Class SimpleControl
    Inherits System.Web.UI.WebControls.WebParts.WebPart

    Private _text As String = "Simple control text"

    Public Property [Text]() As String
      Get
        If Not (_text Is Nothing) Then
          Return _text
        Else
          Return String.Empty
        End If
      End Get
      Set(ByVal value As String)
        _text = value
      End Set
    End Property

    Protected Overrides Sub Render(ByVal writer _
      As System.Web.UI.HtmlTextWriter)

      writer.Write(Me.Text)

    End Sub

  End Class

End Namespace

The second part of the code example is the source code for a derived WebPartZoneBase zone that overrides the OnCreateVerbs method to add a custom verb to the zone. The code also creates a custom verb that appears in the verbs menu of WebPart controls contained in the zone, and the verb creates another copy of the current WebPart control.

Imports System
Imports System.Data
Imports System.Configuration
Imports System.Web
Imports System.Web.Security
Imports System.Security.Permissions
Imports System.Collections.Generic
Imports System.Web.UI
Imports System.Web.UI.WebControls
Imports System.Web.UI.WebControls.WebParts
Imports System.Web.UI.HtmlControls

' This code sample creates a Web Part zone and adds the 
' "Copy Web Part" verb to any control in the zone.
Namespace Samples.AspNet.VB.Controls

  <AspNetHostingPermission(SecurityAction.Demand, _
    Level:=AspNetHostingPermissionLevel.Minimal)> _
  <AspNetHostingPermission(SecurityAction.InheritanceDemand, _
    Level:=AspNetHostingPermissionLevel.Minimal)> _
  Public Class ZoneWithAddedVerb
    Inherits WebPartZone

    'public class ExtendedWebPartZoneBase 
    Protected Overrides Sub OnCreateVerbs(ByVal e _
      As WebPartVerbsEventArgs)

      Dim newVerbs As List(Of WebPartVerb) = _
        New List(Of WebPartVerb)
      newVerbs.Add(New CopyWebPartVerb(AddressOf CopyWebPartToNewOne))
      e.Verbs = New WebPartVerbCollection(e.Verbs, newVerbs)
      MyBase.OnCreateVerbs(e)

    End Sub 'OnCreateVerbs


    Sub CopyWebPartToNewOne(ByVal sender As Object, _
      ByVal e As WebPartEventArgs)

      Dim wpmgr As WebPartManager = _
        WebPartManager.GetCurrentWebPartManager(Page)
      Dim wp As System.Web.UI.WebControls.WebParts.WebPart
      Dim tp As Type = e.WebPart.GetType()
      wp = CType(Activator.CreateInstance(tp), _
        System.Web.UI.WebControls.WebParts.WebPart)
      wpmgr.AddWebPart(wp, e.WebPart.Zone, e.WebPart.ZoneIndex + 1)

    End Sub

  End Class


  <AspNetHostingPermission(SecurityAction.Demand, _
    Level:=AspNetHostingPermissionLevel.Minimal)> _
  <AspNetHostingPermission(SecurityAction.InheritanceDemand, _
    Level:=AspNetHostingPermissionLevel.Minimal)> _
  Friend Class CopyWebPartVerb
    Inherits WebPartVerb
    Private Const _copyWebPartImageUrl As String = "~/CopyVerb.ico"

    Friend Sub New(ByVal serverClickHandler As WebPartEventHandler)
      MyBase.New("MyVerb", serverClickHandler)

    End Sub 'NewNew

    Public Overrides Property [Text]() As String
      Get
        Return "Copy Web Part"
      End Get
      Set(ByVal value As String)
      End Set
    End Property

    Public Overrides Property Description() As String
      Get
        Return "This verb will copy this web part control to a " _
               & "new one below"
      End Get
      Set(ByVal value As String)
      End Set
    End Property

    Public Overrides Property Enabled() As Boolean
      Get
        Return MyBase.Enabled
      End Get
      Set(ByVal value As Boolean)
        MyBase.Enabled = value
      End Set
    End Property

    Public Overrides Property ImageUrl() As String
      Get
        Return Me._copyWebPartImageUrl
      End Get
      Set(ByVal value As String)
      End Set
    End Property

  End Class

End Namespace

The third part of the code example is a Web page that hosts the derived zone and WebPart control. Near the top of the page is a Register directive to reference the derived zone component. If you load the page in a browser, the WebPart control appears in the zone. Click the verbs menu, then click the CopyWebPart verb, and it creates a copy of the control.

<%@ Page Language="VB" %>
<%@ Register TagPrefix="verbsample" 
    namespace="Samples.AspNet.VB.Controls" %>

<!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>Untitled Page</title>
</head>
<body>
    <form id="form1" runat="server">
    <asp:WebPartManager ID="WebPartManager1" runat="server" />
    <verbsample:ZoneWithAddedVerb id="ZoneWithAddedVerb1" 
      HeaderText="Zone with Added Verb" runat="server">
        <ZoneTemplate>
           <verbsample:SimpleControl id="SimpleControl1" 
            title="Simple Control" runat="server" /> 
        </ZoneTemplate>
        </verbsample:ZoneWithAddedVerb>
     </form>
</body>
</html>

.NET Framework
Available since 2.0
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