Make a javascript canvas rectangle clickable -

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i creating simple calculator. here is. done basic design confused on how make buttons clickable? 1 trick make div each button think there has simple way. please guide. 

<!doctype html> <html> <body>  <canvas id="mycanvas" width="300" height="400" style="border:2px solid ;"> browser not support html5 canvas tag.</canvas>  <script>  var c=document.getelementbyid("mycanvas"); var ctx=c.getcontext("2d"); ctx.moveto(0,80); ctx.lineto(300,80); ctx.fillstyle="#333333"; ctx.fillrect(0,320,50,80);  ctx.fillstyle="#333333"; ctx.fillrect(250,320,50,80); ctx.stroke();  </script>  </body> </html>

you can “press” drawn key on canvas listening mouseclicks , hittesting whether click position inside 1 of calculator key’s boundary.

here code return true if mouseclick inside rectangle:

function ispointinsiderect(pointx,pointy,rectx,recty,rectwidth,rectheight){     return  (rectx <= pointx) && (rectx + rectwidth >= pointx) &&                  (recty <= pointy) && (recty + rectheight >= pointy); }

if calculator buttons round, here code hittest mouseclick inside circle:

function ispointinsidecircle(pointx,pointy,circlex,circley,radius){     var dx=circlex-pointx;     var dy=circley-pointy;     return  ( dx*dx+dy*dy<=radius*radius  ); }

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