prepopulate textbox with variable, asp.net
<p>I'd like to prepopulate my textfield with the following variable:</p>

<pre><code>&lt;%=Membership.GetUser().Email%&gt; 
</code></pre>

<p>... so that users can submit their email address to my table without having to type it in.</p>

<p>Here is my code:</p>

<pre><code>&lt;form id="form1" runat="server"&gt;
    &lt;div&gt;
        &lt;!-- This is the code for the form. There is a Text Box to collect the first name, 
            last name and email address. All fields are required and I am validating that the 
            email address is a valid format. --&gt;
        &lt;asp:Table ID="Table1" runat="server"&gt;
            &lt;asp:TableRow&gt;
                &lt;asp:TableCell&gt;First Name: &lt;asp:TextBox ID="txtFirstName" 
                    runat="server" Width="60" /&gt; &lt;asp:RequiredFieldValidator ID="RequiredFieldValidator1" 
                    ErrorMessage="Enter First Name" Text="*" ControlToValidate="txtFirstName" 
                    runat="server" /&gt;
                &lt;/asp:TableCell&gt;
                &lt;asp:TableCell&gt;Last Name: &lt;asp:TextBox ID="txtLastName" runat="server" Width="60" /&gt; 
                    &lt;asp:RequiredFieldValidator ID="RequiredFieldValidator2" runat="server" 
                    ControlToValidate="txtLastName" ErrorMessage="Enter Last Name" Text="*" /&gt;
                &lt;/asp:TableCell&gt;
            &lt;/asp:TableRow&gt;
            &lt;asp:TableRow&gt;
                &lt;asp:TableCell&gt;Email: &lt;asp:TextBox ID="txtEmail" runat="server" Width="80" /&gt;
                    &lt;asp:RequiredFieldValidator ID="emailRequired" 
                        runat="server" ControlToValidate="txtEmail" ErrorMessage="Email Needs Information" 
                        Text="*"/&gt;
                    &lt;asp:RegularExpressionValidator ID="emailexpression" 
                        runat="server" ControlToValidate="txtEmail" ValidationExpression=".*@.*\..*" 
                        ErrorMessage="Invalide Email Address" Text="*" /&gt;
                &lt;/asp:TableCell&gt;
            &lt;/asp:TableRow&gt;
            &lt;asp:TableRow&gt;
                &lt;asp:TableCell&gt;
                    &lt;asp:ValidationSummary ID="ValidationSummary1" runat="server" ShowSummary="true" 
                        ShowMessageBox="true" runat="server" /&gt;
                &lt;/asp:TableCell&gt;
            &lt;/asp:TableRow&gt;
            &lt;asp:TableRow&gt;
                &lt;asp:TableCell&gt;&lt;asp:Button ID="btnSubmit" runat="server" OnClick="addMember" 
                    CausesValidation="true" Height="30" Width="100" Text="Add Me" /&gt;
                &lt;/asp:TableCell&gt;
            &lt;/asp:TableRow&gt;
            &lt;asp:TableRow&gt;
                &lt;asp:TableCell&gt;
                    &lt;asp:Label ID="lblDuplicate" runat="server" Text=""&gt;&lt;/asp:Label&gt;
                &lt;/asp:TableCell&gt;
            &lt;/asp:TableRow&gt;
        &lt;/asp:Table&gt;
    &lt;/div&gt;
&lt;/form&gt;
</code></pre>

<p>How can I accomplish this?</p>
