我目前正在构建一个 HTML5 Web 应用程序 / Phonegap 本地应用程序,我似乎无法弄清楚如何将我的画布保存为canvas.toDataURL()
的图像。
这是代码,有什么问题吗?
/ / 我的画布被命名为“canvasSignature”
JavaScript:
function putImage()
{
var canvas1 = document.getElementById("canvasSignature");
if (canvas1.getContext) {
var ctx = canvas1.getContext("2d");
var myImage = canvas1.toDataURL("image/png");
}
var imageElement = document.getElementById("MyPix");
imageElement.src = myImage;
}
HTML5:
<div id="createPNGButton">
<on onclick="putImage()">Save as Image</on>
</div>

这是一些代码。没有任何错误。
var image = canvas.toDataURL("image/png").replace("image/png", "image/octet-stream"); // here is the most important part because if you dont replace you will get a DOM 18 exception.
window.location.href=image; // it will save locally

此解决方案允许您更改下载文件的名称:
HTML格式:
<a id="link"></a>
JavaScript:
var link = document.getElementById('link');
link.setAttribute('download', 'MintyPaper.png');
link.setAttribute('href', canvas.toDataURL("image/png").replace("image/png", "image/octet-stream"));
link.click();

你可以试试这个;创建一个虚拟的 HTML 锚,并从那里下载图像...
// Convert canvas to image
document.getElementById('btn-download').addEventListener("click", function(e) {
var canvas = document.querySelector('#my-canvas');
var dataURL = canvas.toDataURL("image/jpeg", 1.0);
downloadImage(dataURL, 'my-canvas.jpeg');
});
// Save | Download image
function downloadImage(data, filename = 'untitled.jpeg') {
var a = document.createElement('a');
a.href = data;
a.download = filename;
document.body.appendChild(a);
a.click();
}

您可以使用canvas2image提示下载。
我有同样的问题,这里有一个简单的例子,都将图像添加到页面,并强制浏览器下载它:
<html>
<head>
<script src="http://hongru.github.io/proj/canvas2image/canvas2image.js"></script>
<script>
function draw(){
var canvas = document.getElementById("thecanvas");
var ctx = canvas.getContext("2d");
ctx.fillStyle = "rgba(125, 46, 138, 0.5)";
ctx.fillRect(25,25,100,100);
ctx.fillStyle = "rgba( 0, 146, 38, 0.5)";
ctx.fillRect(58, 74, 125, 100);
}
function to_image(){
var canvas = document.getElementById("thecanvas");
document.getElementById("theimage").src = canvas.toDataURL();
Canvas2Image.saveAsPNG(canvas);
}
</script>
</head>
<body onload="draw()">
<canvas width=200 height=200 id="thecanvas"></canvas>
<div><on onclick="to_image()">Draw to Image</on></div>
<image id="theimage"></image>
</body>
</html>
本站系公益性非盈利分享网址,本文来自用户投稿,不代表码文网立场,如若转载,请注明出处
评论列表(62条)