asp.net ajax技巧--模板面操作內(nèi)容頁面

悟靜 2012-04-30

展開全文

master頁面的前臺
<form id="form1" runat="server">
        <div>
            <asp:ScriptManager ID="ScriptManager1" runat="server" />
            <asp:Panel ID="MasterPanel1" runat="server" GroupingText="主控頁面">
               <asp:Button ID="MasterButton1" runat="server" Text="整頁更新" />
               <asp:Button ID="MasterButton2" runat="server" Text="局部更新" OnClick="MasterButton2_Click" Width="128px" />
            </asp:Panel>
            <asp:ContentPlaceHolder ID="ContentPlaceHolder1" runat="server">
            </asp:ContentPlaceHolder>
        </div>
master頁面的后臺

protected void Page_Load(object sender, EventArgs e)
    {
        ScriptManager1.RegisterAsyncPostBackControl(MasterButton2);
    }

    public DateTime LastUpdate
    {
        get
        {
            if(ViewState["LastUpdate"] == null)
            {
                return DateTime.Now;
            }
            else
            {
                return Convert.ToDateTime(ViewState["LastUpdate"]);
            }
        }
        set
        {
            ViewState["LastUpdate"] = value;
        }
    }

    protected void MasterButton2_Click(object sender, EventArgs e)
    {
        LastUpdate = DateTime.Now;
        UpdatePanel up1 = (UpdatePanel)(ContentPlaceHolder1.FindControl("UpdatePanel1"));
        up1.Update();
    }

注意這里因為希望主頁面的“局部更新”按鈕能引發(fā)異步更新內(nèi)容頁面中的UPDATEPANEL控件的內(nèi)容，因此必須用
ScriptManager1.RegisterAsyncPostBackControl(MasterButton2);
注冊該按鈕引發(fā)的事件。
要注意masterbutton2_click事件的寫法，調(diào)用內(nèi)容頁中的updatepanel控件的UPDATE方法來更新內(nèi)容。
然后在內(nèi)容頁中前臺中

<%@ Page Language="C#" MasterPageFile="~/ThirdMasterPage.master" AutoEventWireup="true"
CodeFile="CH3_DemoForm040.aspx.cs" Inherits="CH3_DemoForm040" Title="如何于主控頁面中使用 UpdatePanel 控件" %>

<%@ MasterType VirtualPath="ThirdMasterPage.master" %>
<asp:Content ID="Content1" ContentPlaceHolderID="ContentPlaceHolder1" runat="Server">
    <asp:Panel ID="Panel2" GroupingText="內(nèi)容頁面" runat="server">
        <asp:UpdatePanel ID="UpdatePanel1" UpdateMode="Conditional" runat="server">
            <ContentTemplate>
                <p>
                    上一次更新：<strong><%= Master.LastUpdate.ToString() %></strong></p>
                <asp:Button ID="ContentButton" OnClick="ContentButton_Click" runat="server" Text="局部更新">
                </asp:Button>
            </ContentTemplate>
        </asp:UpdatePanel>
    </asp:Panel>
</asp:Content>

后臺中，為其“局部更新”編寫相關(guān)的事件，以將當(dāng)前日期時間給主控頁面的lastupdate屬性
protected void ContentButton_Click(object sender, EventArgs e)
    {
        Master.LastUpdate = DateTime.Now;
    }