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WebPartCollection.Item[] Property

Definition

Returns a specific member of the collection according to its position or a unique identifier.

Overloads

Item[Int32]

Returns a member of the collection based on its position in the collection.

Item[String]

Returns a member of the collection based on a unique string identifier.

Item[Int32]

Returns a member of the collection based on its position in the collection.

public:
 property System::Web::UI::WebControls::WebParts::WebPart ^ default[int] { System::Web::UI::WebControls::WebParts::WebPart ^ get(int index); };
public System.Web.UI.WebControls.WebParts.WebPart this[int index] { get; }
member this.Item(int) : System.Web.UI.WebControls.WebParts.WebPart
Default Public ReadOnly Property Item(index As Integer) As WebPart

Parameters

index
Int32

The index of a particular WebPart control in a collection.

Property Value

A WebPart at the specified index in the collection.

Examples

The following code example demonstrates the use of the Item[] indexer on a Web Parts page. This example has three parts:

  • The code for the page in a partial class.

  • The Web page that contains the controls.

  • A description of how the example works in a browser.

The first part of the code example contains the code for the page in a partial class. Note that the Button2_Click method creates an empty WebPartCollection object, then assigns to it the WebPart controls from the WebPartZone1.WebParts property. The method accesses the first control in the collection by using its index, and toggles its Title property value.

using System;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;

public partial class webpartcollectioncs : System.Web.UI.Page
{
  protected void Button1_Click(object sender, EventArgs e)
  {

    WebPartCollection partCollection = mgr1.WebParts;

    foreach (WebPart part in partCollection)
    {
      if (part.ChromeState != PartChromeState.Minimized)
        part.ChromeState = PartChromeState.Minimized;
      else
        part.ChromeState = PartChromeState.Normal;
    }
  }
  protected void Button2_Click(object sender, EventArgs e)
  {
    WebPartCollection partCollection = WebPartZone1.WebParts;

    if (partCollection[0].Title == "My Link List")
      partCollection[0].Title = "Favorite Links";
    else
      partCollection[0].Title = "My Link List";
  }
}
Imports System.Web
Imports System.Web.UI
Imports System.Web.UI.WebControls
Imports System.Web.UI.WebControls.WebParts

Partial Public Class webpartcollectionvb

  Inherits System.Web.UI.Page

  Protected Sub Button1_Click(ByVal sender As Object, ByVal e As System.EventArgs)

    Dim partCollection As WebPartCollection = mgr1.WebParts
    Dim part As WebPart

    For Each part In partCollection
      If part.ChromeState <> PartChromeState.Minimized Then
        part.ChromeState = PartChromeState.Minimized
      Else
        part.ChromeState = PartChromeState.Normal
      End If
    Next

  End Sub

  Protected Sub Button2_Click(ByVal sender As Object, ByVal e As System.EventArgs)

    Dim partCollection As WebPartCollection = WebPartZone1.WebParts

    If partCollection(0).Title = "My Link List" Then
      partCollection(0).Title = "Favorite Links"
    Else
      partCollection(0).Title = "My Link List"
    End If

  End Sub

End Class

The second part of the code example is the Web page that contains the controls. Notice that the controls declared in WebPartZone1 are standard ASP.NET server controls, but because they are wrapped as GenericWebPart controls at run time, and the GenericWebPart class inherits from the WebPart class, the controls can be treated as WebPart controls at run time and made part of a WebPartCollection object.

<%@ Page Language="C#" 
  Codefile="webpartcollection.cs" 
  Inherits="webpartcollectioncs" %>

<!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">
    <div>
      <asp:WebPartManager ID="mgr1" runat="server" />
      <asp:WebPartZone ID="WebPartZone1" runat="server">
        <ZoneTemplate>
          <asp:BulletedList 
            ID="BulletedList1" 
            Runat="server"
            DisplayMode="HyperLink" 
            Title="Favorite Links" >
            <asp:ListItem Value="http://msdn.microsoft.com">
              MSDN
            </asp:ListItem>
            <asp:ListItem Value="http://www.asp.net">
              ASP.NET
            </asp:ListItem>
            <asp:ListItem Value="http://www.msn.com">
              MSN
            </asp:ListItem>
          </asp:BulletedList>
          <br />
          <asp:Calendar ID="Calendar1" runat="server" 
            Title="My Calendar" />
        </ZoneTemplate>
      </asp:WebPartZone>
    </div>
    <hr />
    <asp:Button ID="Button1" runat="server" Width="200"
      Text="Toggle ChromeState" OnClick="Button1_Click" />
    <br />
    <asp:Button ID="Button2" runat="server" Width="200"
        Text="Toggle BulletedList1 Title" 
        OnClick="Button2_Click"/>
    </form>
</body>
</html>
<%@ Page Language="vb"
  Codefile="webpartcollection.vb" 
  Inherits="webpartcollectionvb" %>

<!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 id="Head1" runat="server">
    <title>Untitled Page</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
      <asp:WebPartManager ID="mgr1" runat="server" />
      <asp:WebPartZone ID="WebPartZone1" runat="server">
        <ZoneTemplate>
          <asp:BulletedList 
            ID="BulletedList1" 
            Runat="server"
            DisplayMode="HyperLink" 
            Title="Favorite Links" >
            <asp:ListItem Value="http://msdn.microsoft.com">
              MSDN
            </asp:ListItem>
            <asp:ListItem Value="http://www.asp.net">
              ASP.NET
            </asp:ListItem>
            <asp:ListItem Value="http://www.msn.com">
              MSN
            </asp:ListItem>
          </asp:BulletedList>
          <br />
          <asp:Calendar ID="Calendar1" runat="server" 
            Title="My Calendar" />
        </ZoneTemplate>
      </asp:WebPartZone>
    </div>
    <hr />
    <asp:Button ID="Button1" runat="server" Width="200"
      Text="Toggle ChromeState" OnClick="Button1_Click" />
    <br />
    <asp:Button ID="Button2" runat="server" Width="200"
        Text="Toggle BulletedList1 Title" 
        OnClick="Button2_Click"/>
    </form>
</body>
</html>

After you load the page in a browser, click the Toggle BulletedList1 Title button, and notice that the code toggles the title of the control between the two available title choices.

Remarks

The Item[] indexer allows you to access the underlying WebPart controls in a WebPartCollection object by index, and change their property values or call methods.

See also

Applies to

Item[String]

Returns a member of the collection based on a unique string identifier.

public:
 property System::Web::UI::WebControls::WebParts::WebPart ^ default[System::String ^] { System::Web::UI::WebControls::WebParts::WebPart ^ get(System::String ^ id); };
public System.Web.UI.WebControls.WebParts.WebPart this[string id] { get; }
member this.Item(string) : System.Web.UI.WebControls.WebParts.WebPart
Default Public ReadOnly Property Item(id As String) As WebPart

Parameters

id
String

The unique identifier for a particular WebPart control in a collection.

Property Value

The first WebPart in the collection whose ID equals the value of id.

Remarks

The Item[] indexer enables you to access a WebPart control in a WebPartCollection object according to a unique identifier.

Note

The Web Parts control set performs case-insensitive matching on this property, so case sensitivity is not part of a unique id value.

The Item[] property also works to identify members of a WebPartCollection object in some specialized cases. In the case of GenericWebPart controls, the indexer is able to match the identifier for the underlying child control wrapped by the GenericWebPart control. In the case of ProxyWebPart controls, the indexer matches the identifier for the control based on a case-insensitive comparison of the id parameter and either the OriginalID or GenericWebPartID property values.

See also

Applies to