该方法仅支持IE10+、chrome、等现代浏览器。
适合用于原生支持的(function(){
var Base64 = {
encode : function(str){
return window.btoa(unescape(encodeURIComponent(str)));
},
decode : function(str){
return decodeURIComponent(escape(window.atob(str)));
}
};
window.BASE64 = Base64;
})();
旧版本兼容(function() {
if (!window.btoa) {
var a = “ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=”;
window.btoa = function(c) {
var d = “”;
var m, k, h = “”;
var l, j, g, f = “”;
var e = 0;
do {
m = c.charCodeAt(e++);
k = c.charCodeAt(e++);
h = c.charCodeAt(e++);
l = m >> 2;
j &#