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编码和解码跳过字符

encode decode base64 html javascript

1

Ullas Hunka · 技术社区 · 8 年前

我正在尝试使用编码格式将一些字符串存储到数据库中。但当检索回来时,字符串的格式不正确。

下面是我的代码示例,您很容易看到传递给encode的字符串与解码后的字符串不同。为什么会这样?

有没有其他的库可以帮助我编码和解码?任何关于这一点的建议都是有益的。

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 str = "background:url(/drona-courses/player_assets/skin_0/DRONA_default_skinRightCorner.png) ;"

var encoded = Base64.encode(str);
//console.log(encoded);

var decoded = Base64.decode(encoded);
console.log(str,"......Input");
console.log(decoded,".....Output");

2 回复 | 直到 8 年前

1

2

marpme 8 年前

Base64 Encoding in common browsers

atob()

btoa()

2

1

Sebastian Olsen 8 年前

atob btoa

const foo = "bar"

const encodedFoo = btoa(foo)
const decodedFoo = atob(encodedFoo)

console.log(encodedFoo)
console.log(decodedFoo)

here.