function getScreenDimentions(){
	
		var screenH = screen.height;
   		var screenW = screen.width;
    
    	if(document.all){
        	availW = document.body.clientWidth;
        	availH = document.body.clientHeight;
    	} else{
        	availW = innerWidth; availH = innerHeight;
    	}
    
    	var arrScreenDimentions = new Array(); 	// ALL SIZES ARE WITHOUT 'PX'
    	arrScreenDimentions[0] = screenH		// SCREEN HEIGHT
    	arrScreenDimentions[1] = screenW		// SCREEN WIDTH 
   		arrScreenDimentions[2] = availH			// AVAILABLE HEIGHT
   		arrScreenDimentions[3] = availW			// AVAILABLE WIDTH
    
    	return arrScreenDimentions;
    }

Javascript getScreenDimentions

JavaScript