Question

What is the use of Html.BeginForm in MVC3.
Why do we use it, when we can just add a form tag directly, does this html helper add some capability or does something which cannot be done with a simple form tag.

Answer 1

The Html.BeginForm helper method contains a couple overloads whose intended purpose is to make writing routed forms easier. It is aware of MVC stucture and makes sure its targeting a controller and action. It’s just a bit of syntactic sugar over:

<form method="post" action="@Url.Action(...)">

In Microsoft’s words:

The ASP.NET MVC framework includes helper methods that provide an easy way to render HTML in a view.

Of course, no one is making you use them. Its just a matter of preference. In fact, in the early days of MVC, many WebForms developers celebrated their new freedom from server controls a-la <asp:TextBox> et al., and insisted on writing everything by hand.

Using the helpers for your form fields comes highly recommended, since they’re aware of things like form validation. Html.BeginForm just gives you a consistent way to start and finish your form:

@using(Html.BeginForm())
{
    @Html.LabelFor(...)
    @Html.EditorFor(...)
}

Html.BeginForm returns an IDisposable object, allowing you to wrap it in the C# using statement. When the using exits, the disposal will call Html.EndForm() automatically for you. Since Html.EndForm returns void it is slightly inconvenient to call from Razor:

@Html.BeginForm()
<formStuff>
@{Html.EndForm();}

A simple @Html.EndForm() will turn in to Write(Html.EndForm()) -> Write(void), ie compile time error.