javascript - Canvas not supported in IE fires an exception -

i have canvas element:

<canvas  id="canvas" width="300" height="300">     canvas not supported </canvas>  

code in .js file:

var ct= document.getelementbyid('canvas'); var ctx = document.getelementbyid('canvas').getcontext('2d'); 

but when load in old versions of ie fires exception method getcontext not supported.

what want write this:

if (!ctx.getcontext) ctx = { getcontext: function () { } }; 

to rid of exception in ie. should do?

your condition badly structured, , it's hard see plan - going check getcontext() returns every time call it? why not check whether or not exists in first place:

var ct= document.getelementbyid('canvas'); if ('getcontext' in ct) {     var ctx = ct.getcontext('2d');     //rest of code } 

alternatively try 1 of answers this question, or use modernizr feature detection needs.