通过JS实现Base64在线加密/解密方法

正文:

本篇文章给大家介绍一下在JS当中该如何对字符串进行base64加密，首先我们得引入一个类库才行，具体代码:

// 创建Base64对象
	var Base64 = {
		_keyStr: "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=",
		encode: function(e) {
			var t = "";
			var n, r, i, s, o, u, a;
			var f = 0;
			e = Base64._utf8_encode(e);
			while (f < e.length) {
				n = e.charCodeAt(f++);
				r = e.charCodeAt(f++);
				i = e.charCodeAt(f++);
				s = n >> 2;
				o = (n & 3) << 4 | r >> 4;
				u = (r & 15) << 2 | i >> 6;
				a = i & 63;
				if (isNaN(r)) {
					u = a = 64
				} else if (isNaN(i)) {
					a = 64
				}
				t = t + this._keyStr.charAt(s) + this._keyStr.charAt(o) + this._keyStr.charAt(u) + this._keyStr
					.charAt(a)
			}
			return t
		},
		decode: function(e) {
			var t = "";
			var n, r, i;
			var s, o, u, a;
			var f = 0;
			e = e.replace(/[^A-Za-z0-9+/=]/g, "");
			while (f < e.length) {
				s = this._keyStr.indexOf(e.charAt(f++));
				o = this._keyStr.indexOf(e.charAt(f++));
				u = this._keyStr.indexOf(e.charAt(f++));
				a = this._keyStr.indexOf(e.charAt(f++));
				n = s << 2 | o >> 4;
				r = (o & 15) << 4 | u >> 2;
				i = (u & 3) << 6 | a;
				t = t + String.fromCharCode(n);
				if (u != 64) {
					t = t + String.fromCharCode(r)
				}
				if (a != 64) {
					t = t + String.fromCharCode(i)
				}
			}
			t = Base64._utf8_decode(t);
			return t
		},
		_utf8_encode: function(e) {
			e = e.replace(/rn/g, "n");
			var t = "";
			for (var n = 0; n < e.length; n++) {
				var r = e.charCodeAt(n);
				if (r < 128) {
					t += String.fromCharCode(r)
				} else if (r > 127 && r < 2048) {
					t += String.fromCharCode(r >> 6 | 192);
					t += String.fromCharCode(r & 63 | 128)
				} else {
					t += String.fromCharCode(r >> 12 | 224);
					t += String.fromCharCode(r >> 6 & 63 | 128);
					t += String.fromCharCode(r & 63 | 128)
				}
			}
			return t
		},
		_utf8_decode: function(e) {
			var t = "";
			var n = 0;
			var r = c1 = c2 = 0;
			while (n < e.length) {
				r = e.charCodeAt(n);
				if (r < 128) {
					t += String.fromCharCode(r);
					n++
				} else if (r > 191 && r < 224) {
					c2 = e.charCodeAt(n + 1);
					t += String.fromCharCode((r & 31) << 6 | c2 & 63);
					n += 2
				} else {
					c2 = e.charCodeAt(n + 1);
					c3 = e.charCodeAt(n + 2);
					t += String.fromCharCode((r & 15) << 12 | (c2 & 63) << 6 | c3 & 63);
					n += 3
				}
			}
			return t
		}
	}

var string = 'Hello World!';
// 加密方法
var jiami = Base64.encode(string);
console.log(jiami); // 输出: "SGVsbG8gV29ybGQh"
// 解密方法
var jiemi = Base64.decode(encodedString);
console.log(jiemi); // 输出: "Hello World!"

好了，以上就是本篇文章的全部内容了，希望能够帮助到大家。