Question

My problem is that when I am clicking on button, callfunction() method called and counter is incremented by 5, when I am again click counter incremented by 5 and displayed 10 on given location my problem is that when counter is incremented previous number is not erased and displayed incremented number on previous number. I want to remove previous number and display next incremented number. I have following code:

var count=0;
function callfunction()
   {
         context.fillText(count,200,200);
         count = count+5;
         //context.fillText("",200,200);
   }

Answer 1

fillText with background colour, if it’s monochromatic. Or preserve what was there before as image data, then paste it over later when you want to erase the text.