createdMqttHex static method
通过mqttData生成mqtt发送的消息
Implementation
static String createdMqttHex(MqttData mqttData) {
int length = mqttData.data!.length;
String hexLength = length.toRadixString(16);
hexLength = ("0000" + hexLength).substring(("0000" + hexLength).length - 4);
String data = mqttData.start +
mqttData.messageNumber! +
mqttData.messageType!.type +
mqttData.secretKey! +
hexLength +
mqttData.data!;
return data + calculatedChecksum(data);
}