How to handle an edit and delete button on the same form in ASP.NET MVC?

First of all. Every modification request should be use the post method.
I make some R&D and build the basics of a multi submit button handler in a wiki A clean solution to use multiple submit button in ASP.NET MVC.
I think it could solve your problem.

The best and easiest way would be to use two forms but don't nest them:

<h2>Edit SAS Program</h2>
@using (Html.BeginForm("Edit", "SasProgram", FormMethod.Post))
{
    <label for="Name">Name</label>
    @Html.TextBoxFor(model => model.Name)

    <input type="submit" class="button" value="Save Changes" />
}

@using (Html.BeginForm("Delete", "SasProgram", FormMethod.Post))
{
    <input type="submit" class="button" value="Delete" />
}

This way you have:

• Two separate forms
• No GET requests
• The delete button below the edit button, which makes more sense when you're on a view that allows you to edit something.

I would use different values for button name in the same form:

@using (Html.BeginForm("Edit", "SasProgram", FormMethod.Post))
{
    <label for="Name">Name</label>
    @Html.TextBoxFor(model => model.Name)

    <button name="action" value="delete">Delete</button>
    <button name="action" value="save">Save Changes</button>
}

and then switch in controller:

[HttpPost]
public ActionResult Edit( SomeModel model, string action )
{
    switch( action ) {
        case "delete":
            // delete action
            break;
        case "save":
            // save action
            break;
    }
}

The code is written from memory but it works in production. Note that buttons are of default type - submit.