为继承masterpage的页面设置defaultbutton和defaultfocus

一个普通的aspx页面，我们可以很容易地为其设置设置defaultbutton和defaultfocus，具体如下：

.aspx:

<form id="form1" runat="server">

<div>

<asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>

<asp:Button ID="Button1" Text="Button1" runat="server" OnClick="Button1_Click"></asp:Button>

<asp:Button ID="SubmitButton" Text="Submit" runat="server" OnClick="SubmitButton_Click">

</asp:Button>

</div>

</form>

.cs:

protected void Page_Load(object sender, EventArgs e)

{

this.Form.DefaultButton = SubmitButton.ID ;

this.Form.DefaultFocus = TextBox1.ID;

}

但是如果我们的页面是继承于一个masterpage的，形如：

.aspx:

<asp:Content ID="Content1" ContentPlaceHolderID="ContentPlaceHolder1" runat="Server">

<asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>

<asp:Button ID="Button1" Text="Button1" runat="server" OnClick="Button1_Click"></asp:Button>

<asp:Button ID="SubmitButton" Text="Submit" runat="server" OnClick="SubmitButton_Click">

</asp:Button>

</asp:Content>

.cs:

protected void Page_Load(object sender, EventArgs e)

{

this.Form.DefaultButton = SubmitButton.ID;

this.Form.DefaultFocus = TextBox1.ClientID;

}

在执行时就会提示出现“The DefaultButton of 'form1' must be the ID of a control of type IButtonControl. ”的异常；解决的办法是：在这个页面，用一个panel控件把textbox, button包起来，比如：

.aspx:

<asp:Content ID="Content1" ContentPlaceHolderID="ContentPlaceHolder1" runat="Server">

<asp:panel id="panel" runat="server">

<asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>

<asp:Button ID="Button1" Text="Button1" runat="server" OnClick="Button1_Click"></asp:Button>

<asp:Button ID="SubmitButton" Text="Submit" runat="server" OnClick="SubmitButton_Click">

</asp:Button>

</asp:panel>

</asp:Content>

.cs:

protected void Page_Load(object sender, EventArgs e)

{

panel.DefaultButton = SubmitButton.ID;

this.Form.DefaultFocus = TextBox1.ClientID;

}