SharePoint 2007 : Custom Field Type

Question

I'm trying to create a custom field type in SharePoint 2007, and the steps I did as below:

i) Create a Class Library project in Visual Studio. The code:

public class CustomField : SPFieldText
{
    public CustomField(SPFieldCollection fields, string fName)
        : base(fields, fName)
    {
    }

    public CustomField(SPFieldCollection fields, string tName, string dName)
        : base(fields, tName, dName)
    {
    }

    public override string DefaultValue
    {
        get
        {
            return "XXX";
        }
    }

    public override string  GetValidatedString(object value)
    {
        return value.ToString().ToUpper();
    }
}

ii) registered the project as strong key name
iii) build project, then drag and drop the dll into GAC
iv) create a XML file, the code:

<FieldTypes>
  <FieldType>
    <Field Name="TypeName">CustomField</Field>
    <Field Name="ParentType">Text</Field>
    <Field Name="TypeDisplayName">Custom Field</Field>
    <Field Name="TypeShortDescription">My Custom Field</Field>
    <Field Name="UserCreatable">TRUE</Field>
    <Field Name="FieldTypeClass">ProjectName, CustomField, Version=1.0.0.0, Culture=neutral, PublicKeyToken=XXXPUBLICKEYXXX</Field>
  </FieldType>
</FieldTypes>

v) do iisreset

then I go to SharePoint create a Site Column, I don't see the custom field type I deployed, am I missing any step?

Answer 1

I'd recommend you to use WSP Builder item template for creating Custom Field Types. Just add a project item, and all necessary files will be created automatically.

If you don't want to use WSP Builder, please consider these points:

1. XML files for custom field types should be named as "fldtypes_YourFieldName" and placed into TEMPLATE\XML folder.

2. Looks like you need to swap ProjectName and CustomField in your FieldTypeClass property, to make it look like this:

   <Field Name="FieldTypeClass">MyProject.MyFieldTypeClass, MyProject, Version=1.0.0.0, Culture=neutral, PublicKeyToken=XXXPublicKeyTokenXXX</Field>

3. Usually you should provide also FieldControl and field editor control classes

Also, have a look at following MSDN article:

• Walkthrough: Creating a Custom Field Type