AWS SDK for .NET Documentation
MessageStructure Property
AmazonAmazon.SimpleNotificationService.ModelPublishRequestMessageStructure Did this page help you?   Yes   No    Tell us about it...
The structure of the message. Optional parameter. It can have only one valid value: "json".
Declaration Syntax
C#
public string MessageStructure { get; set; }
Remarks

If this field is set to "json", the value of Message must be a syntactically valid JSON object. It must contain at least a top level JSON key of "default" with a value that is a string. For any other top level key that matches one of our transport protocols (e.g. "http"), the corresponding value (if it is a string) will be used for the message published for that protocol.

Constraints: Keys in the JSON object that correspond to supported transport protocols must have simple JSON string values. The values will be parsed (unescaped) before they are used in outgoing messages. Typically, outbound notifications are JSON encoded (meaning, the characters will be reescaped for sending). JSON strings are UTF-8. Values have a minimum length of 0 (the empty string, "", is allowed). Values have a maximum length bounded by the overall message size (so, including multiple protocols may limit message sizes). Non-string values will cause the key to be ignored. Keys that do not correspond to supported transport protocols will be ignored. Duplicate keys are not allowed. Failure to parse or validate any key or value in the message will cause the Publish call to return an error (no partial delivery).

Assembly: AWSSDK (Module: AWSSDK) Version: 1.5.60.0 (1.5.60.0)