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The GetUserAtHost function takes a Uniform Resource Indicator (URI) string and extracts the user@hostname, if present. If a user@hostname value is not present, the function returns null.


string GetUserAtHost(
  uri uri


  • uri
    A SIP URI whose hostname portion is returned. The function accepts only a valid SIP URI string in the following form: "Display Name" <sip:user@host:port;param=value\> where "Display Name", :port and ;param=value are optional. For example, GetUserAtHost("") returns the string "".

Return Values

Returns a string in the form user@hostname. Returns null if the requested data is not found or if the URI passed in is not a valid SIP URI in the form specified above. Live Communications Server 2003 applications that pass non-SIP URI strings to this function need to be modified to work properly with Office Communications Server 2007.