[SOLVED] Send json with mqtt command

Setup, Configuration and Use Scripts & Rules
2

Easy:

rule "heater time adjust Mode 2"
when
Item progr received command
then
//I want to change the payload values like Arm 1 or 0, Mode 1 or 2 etc 
//but how can i create/compose the json string to send it? because i can't send it with this form above like a simple string

var jsonString = "{\"Arm\":" + ArmItem.state.toString
jsonString = jsonString + ",\"Mode\":" + modeItem.state.toString
jsonString = jsonString + ",\"Time\":\"-2:23\",\"Window\":0,\"Days\":\"11TW11S\",\"Repeat\":1,\"Output\":1,\"Action\":1}"

heater_command.sendCommand(jsonString)

end