what MustUnderstand = true does ? RRS feed

  • Question

  • [MessageContract]
    public class FileDownloadMessage
    [MessageHeader(MustUnderstand = true)]
    public FileMetaData FileMetaData;

    what MustUnderstand = true does ?

    Monday, December 26, 2016 8:42 PM


  • Hi Mou_inn,

    MessageHeaderAttribute.MustUnderstand specifies whether the node acting in the Actor role must understand this header. This is mapped to the mustUnderstand SOAP header attribute. If a header with the mustUnderstand SOAP header attribute set to true is received by Windows Communication Foundation (WCF), it must be a part of the message contract (or must be processed by one of the Windows Communication Foundation (WCF) channels); otherwise, it is assumed that the header is not understood and an exception is thrown.

    I suggest refer below link for complete description with a sample demo.

    # What is the purpose of MustUnderstand property in WCF?

    Best Regards,


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    • Marked as answer by Sudip_inn Wednesday, December 28, 2016 9:10 PM
    Tuesday, December 27, 2016 3:11 AM