ViewCollection.AddAt(Int32, Control) 方法
定义
重要
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将指定的 View 控件添加到集合中的指定索引位置。
public:
override void AddAt(int index, System::Web::UI::Control ^ v);public override void AddAt (int index, System.Web.UI.Control v);override this.AddAt : int * System.Web.UI.Control -> unitPublic Overrides Sub AddAt (index As Integer, v As Control)参数
例外
v 参数不指定 View 控件。
示例
下面的代码示例演示如何以编程方式将控件添加到ViewMultiView控件。 创建每个View控件后，AddAt该方法用于将控件添加到ViewViewCollection指定索引处控件MultiView的集合。 索引Item[]器用于访问ID存储在集合中的ViewCollection控件的属性View，并将其显示给用户。
<%@ 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>
<title>ViewCollection example</title>
<script runat="server">
Sub Button1_Click(ByVal Sender As Object, ByVal e As EventArgs)
' Create a MultiView control.
Dim MultiView1 As New MultiView
' Create a ViewCollection for the View
' controls contained in MultiView1.
Dim myViewCollection As New ViewCollection(MultiView1)
' Create a View control.
Dim View1 As New View
' Use a helper function to create the view.
View1 = CreateView("View1")
' Add View1 to myViewCollection at index 0.
myViewCollection.AddAt(0, View1)
' Create a second View control and
' add it to myViewCollection at index 1.
Dim View2 As New View
View2 = CreateView("View2")
myViewCollection.AddAt(1, View2)
' Create a third View control and
' add it to myViewCollection at index 0.
' Inserting View3 at index 0
' causes View1 to move to index 1
' and View2 to move to index 2.
Dim View3 As New View
View3 = CreateView("View3")
myViewCollection.AddAt(0, View3)
' Show the contents of myViewCollection on the page.
DisplayViewCollectionContents(myViewCollection)
End Sub
' A function to programmatically create a View control.
Private Function CreateView(ByVal viewId As String) As View
' Create a View control
Dim myView As New View
myView.ID = viewId
' Create a Panel control.
Dim Panel1 As New Panel
' Set the style properties for Panel1.
Panel1.Height = New Unit(150)
Panel1.Width = New Unit(150)
Panel1.BackColor = System.Drawing.Color.Azure
Panel1.BorderStyle = BorderStyle.Double
' Add Panel1 to the Controls collection
' of the View control.
myView.Controls.Add(Panel1)
' Create a Label control.
Dim Label1 As New Label
' Set the properties for Label1.
Label1.Text = "This is " + CStr(myView.ID)
' Add Label1 to the Controls collection
' of the Panel1 control.
Panel1.Controls.Add(Label1)
Return myView
End Function
' A sub-routine to display the contents of myViewCollection.
Sub DisplayViewCollectionContents(ByVal collection As ViewCollection)
' Use the Item property to access the ID of the View
' control at the specified index in the collection.
Label1.Text = "The view at index 0 is " + collection.Item(0).ID
Label2.Text = "The view at index 1 is " + collection.Item(1).ID
Label3.Text = "The view at index 2 is " + collection.Item(2).ID
End Sub
</script>
</head>
<body>
<form id="Form1" runat="server">
<h3>ViewCollection example</h3>
<asp:Button id="Button2"
Text="Show ViewCollection contents"
OnClick="Button1_Click"
runat="Server"/>
<br /><br />
<hr />
<asp:Label ID="Label1"
runat="Server">
</asp:Label><br /><br />
<asp:Label ID="Label2"
runat="Server">
</asp:Label><br /><br />
<asp:Label ID="Label3"
runat="Server">
</asp:Label><br /><br />
</form>
</body>
</html>
注解
该方法 AddAt 将新控件添加到集合中的指定索引位置。 该控件只能是控件 View 的实例。
若要在序号索引数组末尾添加控件，请使用 Add 该方法。