Copies the object if it has not been modified since the specified time, otherwise returns a PreconditionFailed.
            
 Declaration Syntax
 Declaration Syntax| C# | 
[ObsoleteAttribute("The With methods are obsolete and will be removed in version 2 of the AWS SDK for .NET. See http://aws.amazon.com/sdkfornet/#version2 for more information.")] public CopyPartRequest WithUnmodifiedSinceDate( DateTime unmodifiedSinceDate )
 Parameters
 Parameters- unmodifiedSinceDate (DateTime)
- The date/time to check the modification timestamp against
 Return Value
 Return Valuethis instance
 Remarks
 Remarks
            Copies the object if it hasn't been modified since the
            specified time; otherwise returns a 412 (precondition failed).
            Constraints: This property can be used with ETagToMatch,
            but cannot be used with other conditional copy properties.