var qcanvas = new Qcanvas(
		{
			id:'qcanvas',
			width:500,
			height:500,  
			// mousedown:function(){
			// 	document.getElementById('contextMenu').style.display = 'none';
			// }
		}) 
 		
    qcanvas.qbezierCurve.bezierCurve({
		start:[20,20],
		handler1:[50,80],
		handler2:[100,20],
		end:[200,20],
		width:1,
		like:'<-->',
		color:'red',
		drag:true,
		withText:'我是个三次曲线'
	}) 


qcanvas.qbezierCurve.bezierCurve({
		start:[200,20],
		handler1:[230,80],
		handler2:[300,20],
		end:[400,20],
		width:1,
		like:'<->',
		color:'blue',
		drag:true,
		withText:'我是个三次曲线'
	})