javascript - Canvas not showing -


i've followed tutorials regarding creating canvas, not working , neither rectangle drawn on it. necessity have script in <head>? appreciated!

here's jsfiddle code.

<!doctype html> <html>     <head>         <title>simple animations in html5</title>     </head> <body> <h2> optical illusion </h2> <video id="illusion" width="640" height="480" controls>     <source src="illusion_movie.ogg"> </video>  <div id="buttonbar">      <button onclick="changesize()">big/small</button> </div>  <p> watch animation 1 minute, staring @ centre of image. @ else near you. few seconds appear distort. source: <a href="http://en.wikipedia.org/wiki/file:illusion_movie.ogg">wikipedia:illusion     movie</a> </p>  <script>     var myvideo=document.getelementbyid("illusion");     var littlesize = false;     function changesize()     {         myvideo.width = littlesize ? 800 : 400;         littlesize = !littlesize;//toggle boolean     } </script>  <canvas id= "mycanvas " width= "500 " height= "500 ">      style="border:1px solid #000000;"> </canvas>  <script>      var canvas = document.getelementbyid("mycanvas");      var context = canvas.getcontext("2d");      context.fillstyle = "blue";     context.fillrect(20, 50, 200, 100);  </script>  </body> </html>

i've cleaned code had few spaces causing problems.

when use script tag set type attribute:

<script type="text/javascript"> // code here </script>

here's corrected fiddle: http://jsfiddle.net/8bk4y/

edit: pointed out below type attribute not needed html5 doctype.


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