js-图片img转base64格式

1##

<head>
    <meta charset="UTF-8">
    <title></title>
</head>
<body>
    <img src=""  class="img"/>
    <script>
        function getBase64Image(img){
            var canvas=document.createElement("canvas");
            canvas.width=img.width;
            canvas.height=img.height;
            var ctx=canvas.getContext("2d");
            ctx.drawImage(img,0,0,img.width,img.height);
            var ext=img.src.substring(img.src.lastIndexOf(".")+1).toLowerCase();
            var dataUrl=canvas.toDataURL("images/"+ext);
            return dataUrl;
        };
        var img="images/1.png";
        var image=new Image();
        image.src=img;
        image.onload=function(){
            var base64=getBase64Image(image);
            document.getElementsByClassName("img")[0].setAttribute("src",base64)
        }
    </script>
</body>

原文地址:https://www.cnblogs.com/xm0328/p/14082284.html