1、base64转换成图片
function base64DataToBlob(dataUrl){
//去掉url的头，并转换为byte
var bytes = window.atob(urlData.split(',')[1]);
//处理异常,将ascii码小于0的转换为大于0
var ab = new ArrayBuffer(bytes.length);
var ia = new Uint8Array(ab);
for (var i = 0; i < bytes.length; i++) {
ia[i] = bytes.charCodeAt(i);
}
return new Blob( [ab] , {type : 'image/png'});
}
2、图片转换成base64
function ImgToBase64(url, fn) {
var canvas = document.createElement('CANVAS');
var ctx = canvas.getContext('2d');
var img = new Image;
img.crossOrigin = 'Anonymous'; //处理跨域图片
img.src = url;
img.onload = function() {
canvas.height = img.height;
canvas.width = img.width;
ctx.drawImage(img, 0, 0);
var dataURL = canvas.toDataURL( 'image/png');
fn.call(this, dataURL);
canvas = null;
};
}
