The basic steps to receiving and processing a SOAP header are: Create a class deriving from SoapHeader representing the data passed in the SOAP header. Add a member to the XML Web service class or XML Web service client proxy class of the type created in step 1. Apply a SoapHeaderAttribute to the XML Web service method or the corresponding method in the proxy class, specifying the member created in step 2 in the MemberName property. Within the XML Web service method or XML Web service client code, access the MemberName property to process the data sent in the SOAP header. [from msdn ]
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