ETag to be matched as a pre-condition for copying the source object
otherwise returns a PreconditionFailed.
Declaration Syntax| C# |
public string ETagToMatch { get; set; }
Remarks
Copies the object if its entity tag (ETag) matches
the specified tag; otherwise return a 412 (precondition failed).
Constraints: This property can be used with IfUnmodifiedSince,
but cannot be used with other conditional copy properties.