Question

How would I go about adding enctype='multipart/form-data' to a form that is generated by using <% Html.BeginForm(); %>?

Answer 1

As part of htmlAttributes,e.g.

Html.BeginForm(     action, controller, FormMethod.Post, new { enctype='multipart/form-data'}) 

Or you can pass null for action and controller to get the same default target as for BeginForm() without any parameters:

Html.BeginForm(     null, null, FormMethod.Post, new { enctype='multipart/form-data'})