HTML5 用动画的表现形式装载图像 _html5教程技巧

示例使用HTML5的canvas标签和Javascript脚本，简单的编写了装载图片效果，请使用支持HTML5的浏览器预览效果：
下图为以逐渐横向栅格的效果图

html部分：

XML/HTML Code复制内容到剪贴板

1. /span>>
2. html lang="en">
3. head>
4. meta charset="UTF-8">
5. title>html5 装载图片title>
6. head>
7. body>
8. button onclick="drawImg1()">从左到右button>
9. button onclick="drawImg2()">从*到左右两边button>
10. button onclick="drawImg3()">以逐渐横向栅格button>
11. hr/>
12. canvas class="canvas" id="canvas" width="600" height="300">canvas>
13. body>
14. html>

JavaScript部分：
　

XML/HTML Code复制内容到剪贴板

1. 　//初始化
2. var canvas = document.getElementById("canvas"),
3. context = canvas.getContext("2d"),
4. image = new Image();
5. image.src = "img/test.jpg";
6. //从左到右加载方法
7. function drawImg1(){
8. var drawWidth = 0,
9. interval = setInterval(function(){
10. context.drawImage(image, 0, 0, drawWidth, image.height, 0, 0, drawWidth, image.height);
11. drawWidth += 20;
12. if(drawWidth > canvas.width) clearInterval(interval);
13. },100);
14. }
15. //从*向左右两边拉开加载方法
16. function drawImg2(){
17. var drawWidth = 0,
18. drawLeft = canvas.width/2,
19. interval = setInterval(function(){
20. context.drawImage(image, drawLeft, 0, drawWidth, image.height, drawLeft, 0, drawWidth, image.height);
21. drawWidth += 20;
22. drawLeft -= 10;
23. if(drawLeft 0) clearInterval(interval);
24. },100);
25. }
26. //以逐渐横向栅格加载方法
27. function drawImg3(){
28. var drawWidth = 0,
29. spaceWidth = canvas.width/20, //10指分割的块数
30. interval = setInterval(function(){
31. for(var i = 0;i20;i++){
32. context.drawImage(image, i*spaceWidth, 0, drawWidth, image.height, i*spaceWidth, 0, drawWidth, image.height);
33. }
34. drawWidth += 5;
35. if(drawWidth > spaceWidth) clearInterval(interval);
36. },100);
37. }

以上内容是小编给大家介绍的HTML5 用动画的表现形式装载图像，希望对大家有所帮助！