How to make SignUp/Login action in one form - asp.net-mvc

Question

I working on my first ASP.net MVC project and and i got some problems using multiple buttons in one form.
When my user type username&password and then hit login means it will go to welcome page
if user try to Sign Up means it will go to another form field to get Personal information.
and finally all given information need to store in database and redirect user to welcome page .
#using (Html.BeginForm("about", "home", FormMethod.Post, new { #id = "msform" }))
{
#Html.AntiForgeryToken()
#Html.ValidationSummary()
<!-- progressbar -->
<ul id="progressbar">
<li class="active"></li>
<li></li>
<li></li>
</ul>
<!-- fieldsets -->
<fieldset>
<h2 class="fs-title">Create your account</h2>
<h3 class="fs-subtitle">Take 60 Seconds With Us</h3>
<input type="text" name="UsersName" placeholder="Username" />
<input type="password" name="Passsword" placeholder="Password" />
<input type="button" name="next" class="next action-button" value="Sign Up" />
<input type="button" name="next" class="nexts action-login" value="Log In" />
<input type="submit" value="+" />
</fieldset>
<fieldset>
<h2 class="fs-title">Personal Information</h2>
<h3 class="fs-subtitle">We will never share</h3>
<input type="text" name="phone" placeholder="Email" />
<input type="text" name="phone" placeholder="Phone Number" />
<input type="text" name="date" placeholder="Date of Birth" />
<input type="text" name="gender" placeholder="Gender" />
<input type="button" name="previous" class="previous action-button" value="Previous" />
<input type="button" name="next" class="next action-button" value="Next" />
</fieldset>
<fieldset>
<h2 class="fs-title">Make SomeOne Alive</h2>
<h3 class="fs-subtitle">A donor today! A hero tommorow!</h3>
<input type="text" name="fname" placeholder="Blood Group" />
<input type="text" name="lname" placeholder="Are You ?" />
<input type="text" name="phone" placeholder="State" />
<input type="text" name="phone" placeholder="City" />
<input type="button" name="previous" class="previous action-button" value="Previous" />
<input type="submit" name="submit" class="action-button" value="Submit" />
</fieldset>
}
But now that I have a login button placed on my view form, I'm totally lost. I don't know how to make when user click login button means it will redirect ,if signUp means it will redirect to another form. How to implement the form

Answer 1

Give your button names, and then test for their existence in the posted data server-side. Only the one that is clicked will be there:
<button type="submit" name="_SignUp">Sign Up</button>
<button type="submit" name="_LogIn">Log In</button>
Then, in your action:
if (Request.Unvalidated["_SignUp"] != null)
{
// do sign up
}
if (Request.Unvalidated["_LogIn"] != null)
{
// do log in
}
Or, you can alternatively just divine the user's intention, by attempting to retrieve the user object to sign them in, and if you get no match, then doing the signup instead. However, that pretty much makes the buttons unimportant and could result in the user clicking "Sign Up" and actually being logged in, instead, or vice versa. It doesn't really matter, but it's better to manage user's expectations. If they think they don't have an account, but actually do, they might want to know that.