function CustomAlert(){ this.alert = function(message,title){ document.body.innerHTML = document.body.innerHTML + '
'; let dialogoverlay = document.getElementById('dialogoverlay'); let dialogbox = document.getElementById('dialogbox'); let winH = window.innerHeight; dialogoverlay.style.height = winH+"px"; dialogbox.style.top = "100px"; dialogoverlay.style.display = "block"; dialogbox.style.display = "block"; document.getElementById('dialogboxhead').style.display = 'block'; if(typeof title === 'undefined') { document.getElementById('dialogboxhead').style.display = 'none'; } else { document.getElementById('dialogboxhead').innerHTML = ' '+ title; } document.getElementById('dialogboxbody').innerHTML = message; document.getElementById('dialogboxfoot').innerHTML = ''; } this.ok = function(){ document.getElementById('dialogbox').style.display = "none"; document.getElementById('dialogoverlay').style.display = "none"; } } let customAlert = new CustomAlert();