Drawing Ribbon Type Shape On Canvas Element

I've coded in Java before but I'm still having some trouble. I am trying to draw a ribbon type shape on an <canvas> element and for some reason, when I turned it into a function, it seemed not to work. Here is what I have for drawing the ribbon with a function:

function drawRibbon(height,width,Canvas){
var c=document.getElementById(Canvas);
var cxt=c.getContext("2d");
cxt.fillStyle="#bb0044";
cxt.beginPath();
cxt.moveTo(0,0);
cxt.lineTo(0,height-50);
cxt.lineTo((width-20)/2,height-100);
cxt.lineTo((width-20),height-50);
cxt.lineTo(width-20,0);
cxt.shadowOffsetX = 5;
cxt.shadowOffsetY = 10;
cxt.shadowBlur=10;
cxt.shadowColor = "black";
cxt.fill();
cxt.shadowOffsetX = 0;
cxt.shadowOffsetY = 0;
cxt.shadowBlur=0;
cxt.closePath();
cxt.beginPath();
cxt.strokeStyle = "#ffcc22";
for (i=5;i <= 135; i=i+15){
cxt.moveTo(5,i);
cxt.lineTo(5,i+5);
cxt.stroke();
}}
drawRibbon(200,120,navCanvas);

I feel like it has something either to do with the function definition, or the call. Before this script is executed, i create a canvas in the following way:
<canvas id="navCanvas" height="200" width="120">
Why it is not displaying.