Returns metadata for the object only if it has been modified since the specified time, 
            otherwise returns a PreconditionFailed signal.
            
 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 GetObjectMetadataRequest WithModifiedSinceDate( DateTime modifiedSinceDate )
 Parameters
 Parameters- modifiedSinceDate (DateTime)
- Date and time to be tested
 Return Value
 Return Valuethis instance
 Remarks
 Remarks
            When this is set the S3 object metadata is returned only if it has been modified since the specified time, 
            otherwise returns a 304 (not modified).