How to change change value of variable every time when I click on button-CodePudding

I have two variables and I need to add number on value that is already inside variable every time when I click on button.

This is my code:

var x = e.pageX;
var y = e.pageY;

I have x an y variable and I need to add on x 30 and on y 22 every time when I click on button.But right now when I click on button I add this number just once and when I click again nothing happened.

var xLeft = x   30;
var yTop = y   22;

CodePudding user response：

Please check following example

var x = 10
var y = 20
var xLeft=0
var yTop=0

function clickFunction() {
   xLeft  =  x   30
   yTop  =  y   22
   
   console.log("xLeft :"   xLeft)
   console.log("yTop :"   yTop)
}

<!DOCTYPE html>
<html>
<body>

<button type="button" onclick="clickFunction()">Click Me!</button>
 
</body>
</html>

CodePudding user response：

HTML:

<button id="btn" onclick="myfunc()"></button>

js:

    function myfunc() {
      a  = 2
    }