I am working on asp.net application. I have a master page with two sets of textboxes:

```html
<asp:TextBox ID="txtEmail" runat="server"></asp:TextBox>
<div class="loginPswd">                           
    <asp:TextBox ID="txtPassword" TextMode="Password" runat="server"></asp:TextBox><br />
    <a href="javascript:;">Forgot Password?</a>
</div>
<div class="loginBtn">
    <input type="button" name="" value="Sign In" />
    <a href="#signUpModal" id="signupBtn">Sign Up</a>
</div>

```

and 

```html
<div id="signUpModal" style="display: none;" class="modal-example-content">
    <div class="modal-example-header">
        <button type="button" class="close" onclick="$.fn.custombox('close');">&times;</button>
    </div>
    <center>
        <div class="modal-example-body">
            <p>
                Start searching now<br />
                <a style="color:#fff;" href="http://joelinks.com/" target="_blank">.com</a><br />
                Get Started - Its free.
            </p>
            <div>
                <label>First Name</label>
                <%-- <input type="text" value="" name="" /> --%>
                <asp:TextBox ID="TextFirstName" runat="server"></asp:TextBox>
            </div>
            <div>
                <label>Last Name</label>
                <asp:TextBox ID="TextLastName" runat="server"></asp:TextBox>
            </div>
            <div>
                <label>Email</label>
                <asp:TextBox ID="TextEmail" runat="server"></asp:TextBox>
            </div>
            <div>
                <label>Password (6 or more characters)</label>
                <asp:TextBox ID="TextPassword" TextMode="password" runat="server"></asp:TextBox>
            </div>
            <div>
                <label>Retype Password</label>
                <asp:TextBox ID="TextRetypePassword" TextMode="password" runat="server"></asp:TextBox>
            </div>
            <div>
                <label>User</label>
                <asp:DropDownList ID="DropDownUser" runat="server">
                    <asp:listitem text="Business User" Value="3" />
                    <asp:ListItem Text="Individual User" Value="2"></asp:ListItem>
                </asp:DropDownList>
            </div>
            <div>
                <asp:Button ID="JoinNow" runat="server" Text="Join Now" OnClick="JoinNow_Click" UseSubmitBehavior="False"></asp:Button>
            </div>
            <p style="font-weight:normal; margin-top:10px;">
                Already on <a style="color:#fff;" href="http://.com/">JoeLinks.com</a>? <a style="color:#fff;" href="http://.com/">Sign In</a>
            </p>
        </div>
    </center>
</div>

```

I have a `form` element after `body` tag. I have used `Submitbehavor=false` in the textbox of register (second code). When I hit the submit button, it goes to that event in code behind but values of textboxes are not in codebehind. If I don't use submit behavior then it doesn't go to codebehind. Whereas clicking the login button, values are available in codebehind.

How can I fix this ?