How do you create a multi-select people-picker field programatically in SP 2007?

Question

I would like to create a people-picker user field where more than one user can be chosen.

Currently, this is what I'm doing:

SPField field = new SPField(contentType.Fields, "User", "Users");
SPFieldLink fieldLink = new SPFieldLink(field);
contentType.FieldLinks.Add(fieldLink);
contentType.Update();

However, I imagine this only creates a field to select a single user.

Answer 1

Cast it to an SPFieldUser, or create an SPFieldUser in the first place, and set AllowMultipleValues to true.

Answer 2

you can use only AddFieldAsXml because Multiselect User Field is marked as non-UserCreatable :)

list.fields.AddFieldAsXml(<Field Type="UserMulti" DisplayName="My_User_Field" Required="FALSE" UserSelectionMode="PeopleAndGroups" UserSelectionScope="0" Mult="TRUE" Sortable="FALSE" ID="{7293d78b-f9b3-4cce-b85f-ac499fc4fcf2}")