Action script problem

1

i have made a button and I have given it this AS
ActionScript Code:


on (release){
    if (_root.cht="give"){
        _root.cht==""
        _root.inv==true
        _root.chtst=="invincible"
    }
}

I cant get it to where I release the button a seprate dynamice text box equals invincible and that the text box that you typed in (_root.cht) equals nothing. plz help