Gets a field mask for a copied item.
Assembly: Microsoft.SharePoint (in Microsoft.SharePoint.dll)
The SPCopyFieldMask object is used during copy operations. If a field is included in the SPCopyFieldMask object of the destination item, the value of the source item for that field is not written into the destination item. If a field is included in the SPCopyFieldMask object, it is protected from being overwritten by copy operations.