页面生成图片

<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>htmltopic</title>

<script type="text/javascript" src="http://code.jquery.com/jquery-2.1.1.min.js"></script>
<script type="text/javascript" src="https://cdn.bootcss.com/html2canvas/0.5.0-beta3/html2canvas.min.js"></script>


<style>
* {
margin: 0;
}


.test {
width: 100px;
height: 100px;
text-align: center;
line-height: 100px;
background-color: #87CEEB;
display: inline-block;
vertical-align: top;
}


canvas {
margin-right: 5px;
}


.down {
float: left;
margin: 40px 10px;
}
.down2 {
float: left;
margin: 40px 30px;
}
</style>
</head>
<body>


<div class="test">测试</div>
<div><a class="down" href="" download="downImg">下载</a>
</div>
<div><a class="down2" href="" download="downImg">下载2</a></div>
<script>
//直接选择要截图的dom，就能截图，但是因为canvas的原因，生成的图片模糊
//html2canvas(document.querySelector('div')).then(function(canvas) {
// document.body.appendChild(canvas);
//});
//创建一个新的canvas
var canvas2 = document.createElement("canvas");
let
_canvas = document.querySelector('div');
var w = parseInt(window.getComputedStyle(_canvas).width);
var h = parseInt(window.getComputedStyle(_canvas).height);
//将canvas画布放大若干倍，然后盛放在较小的容器内，就显得不模糊了
canvas2.width = w * 2;
canvas2.height = h * 2;
canvas2.style.width = w + "px";
canvas2.style.height = h + "px";
//可以按照自己的需求，对context的参数修改,translate指的是偏移量
// var context = canvas.getContext("2d");
// context.translate(0,0);
var context = canvas2.getContext("2d");
context.scale(2, 2);
html2canvas(document.querySelector('div'), { canvas: canvas2 }).then(function(canvas) {
//document.body.appendChild(canvas);
//canvas转换成url，然后利用a标签的download属性，直接下载，绕过上传服务器再下载
document.querySelector(".down").setAttribute('href', canvas.toDataURL());
});
</script>


<script language="javascript">
//这是另一种写法
$(function () {
$(".down2").click(function () {
html2canvas($(".test")).then(function (canvas) {
var imgUri = canvas.toDataURL("image/png").replace("image/png", "image/octet-stream"); // 获取生成的图片的url
window.location.href = imgUri; // 下载图片
});


//html2canvas($('.tongxingzheng_bg'), {
// onrendered: function (canvas) {
// var data = canvas.toDataURL("image/png");//生成的格式
// //data就是生成的base64码啦
// alert(data);
// }
//});
});
});
</script>
</body>
</html>

使用htmnl2canvas：http://html2canvas.hertzen.com/

优化清晰以及问题解决方案：https://segmentfault.com/a/1190000011478657?utm_source=tag-newest

附：插件更改https://segmentfault.com/a/1190000007707209

这里有一个

html2canvas(html2canvasdiv, {
allowTaint : false,
taintTest : false,
onrendered : function(canvas) {
var dataUrl = canvas.toDataURL();
img.src = dataUrl;

}

});
allowTaint : false这个参数

是网友提供的但是否可行还没去实验

posted on 2018-12-21 15:59 Leegj 阅读(485) 评论(0) 编辑收藏举报