Sometimes we need to access SharePoint built-in fields from list. You may find code to access list item value as shown below:
Code Snippet 1: Usual approach
The title field is SharePoint built-in field and you don’t need to hard-code the field name . SharePoint Object Model provides a class ‘SPBuiltInFieldId'’ where you can find most of the SharePoint built-in field’s IDs. So you can write the above code snippet as shown below:
Code snippet 2: Suggested approach to access built-in fields
The class ‘SPBuiltInFieldId’ also provides many built-in fields Ids like ‘created by’ (known as owner), modified by etc.
Similarly you can get built-in content type Ids using the class ‘SPBuiltInContentTypeId’. I would recommend you to use these classes to access built-in fields and content types.