MultiView和View控件允许您将页面内容划分为不同的组,一次只显示一个组.每个View控件管理一组内容,所有View控件都在MultiView控件中保存在一起.
MultiView控件负责一次显示一个View控件.显示的视图称为活动视图.
MultiView控件的语法是:
<asp:MultView ID= "MultiView1" runat= "server"> </asp:MultiView>
View控件的语法是:
<asp:View ID= "View1" runat= "server"> </asp:View>
但是,View控件本身不能存在.如果您尝试独立使用它会导致错误.它总是与Multiview控件一起使用:
<asp:MultView ID= "MultiView1" runat= "server"> <asp:View ID= "View1" runat= "server"> </asp:View> </asp:MultiView>
View和MultiView控件都派生自Control类并继承其所有属性,方法和事件. View控件最重要的属性是Boolean类型的Visible属性,它设置视图的可见性.
MultiView控件具有以下重要属性:
属性 | 描述 |
---|---|
Views | MultiView中的View控件集合. |
ActiveViewIndex | 表示活动视图的基于零的索引.如果没有活动视图,则索引为-1. |
与该关联的按钮控件的CommandName属性MultiView控件的导航与MultiView控件的某些相关字段相关联.
例如,如果具有CommandName值的按钮控件作为NextView与多视图的导航相关联,则会自动单击按钮时导航到下一个视图.
下表显示了上述属性的默认命令名称:
属性 | 描述 |
---|---|
NextViewCommandName | NextView |
PreviousViewCommandName | PrevView |
SwitchViewByIDCommandName | SwitchViewByID |
SwitchViewByIndexCommandName | SwitchV iewByIndex |
多视图控件的重要方法是:
方法 | 描述 |
---|---|
SetActiveview | 设置活动视图 |
GetActiveview | 检索活动视图 |
每次更改视图时,页面都会回发到服务器并引发一些事件.一些重要的事件是:
活动 | 描述 |
---|---|
ActiveViewChanged | 视图已更改 |
Activate | 由活动视图引发 |
Deactivate | 由非活动视图提出 |
除了上面提到的属性,方法和事件,多视图控件还继承了控件和对象类的成员.
示例页面有三个视图.每个视图都有两个用于浏览视图的按钮.
内容文件代码如下:
<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="Default.aspx.cs" Inherits="multiviewdemo._Default" %> <!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> <h2>MultiView and View Controls</h2> <asp:DropDownList ID="DropDownList1" runat="server" onselectedindexchanged="DropDownList1_SelectedIndexChanged"> </asp:DropDownList> <hr /> <asp:MultiView ID="MultiView1" runat="server" ActiveViewIndex="2" onactiveviewchanged="MultiView1_ActiveViewChanged" > <asp:View ID="View1" runat="server"> <h3>This is view 1</h3> <br /> <asp:Button CommandName="NextView" ID="btnnext1" runat="server" Text = "Go To Next" /> <asp:Button CommandArgument="View3" CommandName="SwitchViewByID" ID="btnlast" runat="server" Text ="Go To Last" /> </asp:View> <asp:View ID="View2" runat="server"> <h3>This is view 2</h3> <asp:Button CommandName="NextView" ID="btnnext2" runat="server" Text = "Go To Next" /> <asp:Button CommandName="PrevView" ID="btnprevious2" runat="server" Text = "Go To Previous View" /> </asp:View> <asp:View ID="View3" runat="server"> <h3> This is view 3</h3> <br /> <asp:Calendar ID="Calender1" runat="server"></asp:Calendar> <br /> <asp:Button CommandArgument="0" CommandName="SwitchViewByIndex" ID="btnfirst" runat="server" Text = "Go To Next" /> <asp:Button CommandName="PrevView" ID="btnprevious" runat="server" Text = "Go To Previous View" /> </asp:View> </asp:MultiView> </div> </form> </body> </html>
观察以下内容:
MultiView.ActiveViewIndex确定将显示哪个视图.这是在页面上呈现的唯一视图.当没有显示视图时,ActiveViewIndex的默认值为-1.由于ActiveViewIndex在示例中定义为2,因此在执行时会显示第三个视图.