Fixed #5387 -- Added is_multipart method to forms. Original patch from Petr Marhhoun. Tests and documentation from Murkt.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@6273 bcc190cf-cafb-0310-a4f2-bffc1f526a37

docs/newforms.txt

@@ -776,6 +776,27 @@ form data *and* file data::
     # Unbound form with a image field
     >>> f = ContactFormWithMugshot()
 
+Testing for multipart forms
+~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+If you're writing some reusable views or templates, you may not know ahead of
+time whether your form is a multipart form or not. The ``is_multipart()``
+method tells you if the form requires multipart encoding for submission::
+
+    >>> f = ContactFormWithMugshot()
+    >>> f.is_multipart()
+    True
+
+In a template, this sort of code could be useful::
+
+    {% if form.is_multipart %}
+      <form enctype="multipart/form-data" method="post" action="/foo/">
+    {% else %}
+      <form method="post" action="/foo/">
+    {% endif %}
+    {% form %}
+    </form>
+
 Subclassing forms
 -----------------