public bool Put[Type]( [Type] obj, bool overwrite )
Above, [Type] is a placeholder for the class name of the desired object.
The DataSource has a 'Put' method for each type of object that can reside in the data source. The 'Put' method will add an item to the data source or change the value of an item in the data source. For example, in order to add a new AngularUnit to the data source, one would use the PutAngularUnit method, and to add a new HorizontalDatum to the data source, one would use the PutHorizontalDatum method.
The Put methods take two arguments. The first argument is the object to be put in the data source, and the second is a boolean value indicating if an existing object in the data source should be overwritten to accommodate the specified object. A true value will overwrite an existing object with identifiers that match the specified object, and a false value will leave the existing object in the data source.
If the object being edited already exists in the base datasource and the Editable property is false, then this method will cause a GeoCalcException to be thrown with ErrorCode specifying FileReadOnly.