{'Title':taskName,'StartDate':sDate,'Priority':priority, Assigned_x0020_To':assigned}
{'Title':taskName,'StartDate':sDate,'Priority':priority, Assigned_x0020_To':assigned}
For details about how to work with special fields like lookup, user, or URL refer to SPlusBridgeDataType.
{filename1:'add',filename2:'update',filename3:'remove',filename4:'add'}