[ASK AS2] How to make an Input Text trigger an action?

I want to trigger an action when changing value in Input Text any time with this code

inTempSP.onChanged=function(){
        if(vTempSP>100){trace("Temperatur over heat")};
        if(vTempSP<100){trace("Temperatur OK")};
    }

But i don’t know that code is not working well. Any help pleaseeee ??

Note:
inTempSP = Instant name of Input Text
vTempSP = Variable name of Input Text