js将图片转化为base64

参考地址：http://www.cnblogs.com/mr-wuxiansheng/p/6931077.html

var img = "imgurl";//imgurl 就是你的图片路径  

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("image/"+ext);

     return dataURL;

}  

var image = new Image();

image.src = img;

image.onload = function(){

  var base64 = getBase64Image(image);

  console.log(base64);

}  

js将base64转化为图片格式

参考地址：https://segmentfault.com/q/1010000010236626

js直接设置img的src属性为 图片的base64数据即可

document.getElementById('img').setAttribute( 'src', 'data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAUAAAAFCAYAAACNbyblAAAAHElEQVQI12P4//8/w38GIAXDIBKE0 DHxgljNBAAO9TXL0Y4OHwAAAABJRU5ErkJggg==' );