The SendLetter() method is the simplest way to send a letter through the PostalMethods service.
With this method, you must create a letter which includes the address block in its proper location for the envelope type you wish to use. Letter templates are available for the various envelope types that PostalMethods supports.
|Username||String||As provided during registration|
|Password||String||As provided during registration|
|MyDescription||String||Up to 100 characters.
Free text. User may add any text to help identify the request (UTF8)
|FileExtension||String||The extension of the attached document
See List of supported file types
|FileBinaryData||base64Binary||Document to send represented as base64 encoded binary data|
|SendLetterResult||int||In case of successful submission, a positive number is returned indicating the letter's unique identifier on the system.
In case of failure, a negative number is returned indicating the failure reason. See the list of Web Service Result Codes.