asp.net mvc form field contained ,,

Question

My MVC application has a form with many fields. When I submit the empty form, some of the field values returned were ,, (two commas).

string value = form[key];     // value is ,,

I was expecting to see an empty string, not 2 commas.

Answer 1

Turns out the problem was that I had two fields on the form with the same name. MVC must have concatenated the values together comma separated.

Answer 2

When you have multiple fields with the same name the values of the fields will be returned as a comma seperated string. It is mentioned here.

From MSDN:

If your form includes multiple objects with the same name (for example, HTML SELECT tags), the item in the form collection will be a comma-delimited list of all the selected values.