1.HTML5中的Canvas标签的创建

window.onload = function(){ createCanvas(); } function createCanvas(){ var canvas_width= 200, canvas_height = 200; document.body.innerHTML = "<canvas id=\"canvas\" width=\""+canvas_width+"\" height=\""+canvas_height+"\"></canvas>"; }

2.HTML5Canvas标签绘制图形

var canvas_width= 500, canvas_height = 500; var mycanvas, context; window.onload = function(){ createCanvas(); drawRect(); } function createCanvas(){ document.body.innerHTML = "<canvas id=\"mycanvas\" width=\""+canvas_width+"\" height=\""+canvas_height+"\"></canvas>"; mycanvas = document.getElementById("mycanvas"); context = mycanvas.getContext("2d"); } function drawRect(){ context.fillStyle ="#FF0000"; context.fillRect(0,0,200,200); }

3.HTML5Canvas标签绘制图片

var canvas_width= 500, canvas_height = 500; var mycanvas, context; window.onload = function(){ createCanvas(); drawImage(); } function createCanvas(){ document.body.innerHTML = "<canvas id=\"mycanvas\" width=\""+canvas_width+"\" height=\""+canvas_height+"\"></canvas>"; mycanvas = document.getElementById("mycanvas"); context = mycanvas.getContext("2d"); } function drawImage(){ var img = new Image(); img.onload = function(){ context.drawImage(img,0,0); } img.src = "1.png"; }