如何将画布图像保存在磁盘中？

Question

在我的应用程序中，我将两张图像合并为html.now中的单个图像，并将该图像保存到我的磁盘中。但代码工作正常，只有2次，之后，它没有保存image.i试图找到错误，但没有得到任何东西。请帮我把它整理出来。

<p>Image to use:</p> 

<img id="scream" src="img_the_scream.jpg" alt="The Scream" 
width="220" height="277"> 
<img id="scream2" src="img_the_scream.jpg" alt="The Scream" 
width="220" height="277"> 


<p>Canvas to fill:</p> 

<canvas id="canvas" width="800" height="300" 
style="border:1px solid #d3d3d3;"> 
Your browser does not support the HTML5 canvas tag.</canvas> 

<p><button onclick="myCanvas()">Try it</button></p> 

<script> 
function myCanvas() { 
    var c = document.getElementById("canvas"); 
    var ctx = c.getContext("2d"); 
    var img = document.getElementById("scream"); 
    ctx.drawImage(img,10,10); 

var img = document.getElementById("scream2"); 
    ctx.drawImage(img,210,10); 
} 
</script> 
     <h1>Save Image</h1> 


     <button type="button" onclick="saveImage()">save image</button> 
     <script type="text/javascript"> 
      function saveImage() { 
       var ua = window.navigator.userAgent; 

       if (ua.indexOf("Chrome") > 0) { 
        // save image without file type 
        var canvas = document.getElementById("canvas"); 
        document.location.href = canvas.toDataURL("image/png").replace("image/png", "image/octet-stream"); 

        // save image as png 
        var link = document.createElement('a'); 
        link.download = "test1.png"; 
        link.href = canvas.toDataURL("image/png").replace("image/png", "image/octet-stream");; 
        link.click(); 
       } 
       else { 
        alert("Please use Chrome"); 
       } 
      } 
     </script> 

Answer 1

您可以右键单击画布并将图像另存为。