1.前台JS
1 <script type="text/javascript">
2 $(function() {
3 $("#btn").click(function() {
4 var username = encode64($("#username").val()); //对数据加密
5 var password = encode64($("#password").val());
6 $("#username").val(username);
7 $("#password").val(password);
8 document.fm.submit(); //fm为form表单name
9 })
10 })
11
12 // base64加密开始
13 var keyStr = "ABCDEFGHIJKLMNOP" + "QRSTUVWXYZabcdef" + "ghijklmnopqrstuv"
14 + "wxyz0123456789+/" + "=";
15
16 function encode64(input) {
17
18 var output = "";
19 var chr1, chr2, chr3 = "";
20 var enc1, enc2, enc3, enc4 = "";
21 var i = 0;
22 do {
23 chr1 = input.charCodeAt(i++);
24 chr2 = input.charCodeAt(i++);
25 chr3 = input.charCodeAt(i++);
26 enc1 = chr1 >> 2;
27 enc2 = ((chr1 & 3) << 4) | (chr2 >> 4);
28 enc3 = ((chr2 & 15) << 2) | (chr3 >> 6);
29 enc4 = chr3 & 63;
30 if (isNaN(chr2)) {
31 enc3 = enc4 = 64;
32 } else if (isNaN(chr3)) {
33 enc4 = 64;
34 }
35 output = output + keyStr.charAt(enc1) + keyStr.charAt(enc2)
36 + keyStr.charAt(enc3) + keyStr.charAt(enc4);
37 chr1 = chr2 = chr3 = "";
38 enc1 = enc2 = enc3 = enc4 = "";
39 } while (i < input.length);
40
41 return output;
42 }
43 // base64加密结束
44 </script>
2、后台java代码
1 private static char[] base64EncodeChars = new char[] { 'A', 'B', 'C', 'D',
2 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q',
3 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z', 'a', 'b', 'c', 'd',
4 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q',
5 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', '0', '1', '2', '3',
6 '4', '5', '6', '7', '8', '9', '+', '/', };
7
8 private static byte[] base64DecodeChars = new byte[] { -1, -1, -1, -1, -1,
9 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
10 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
11 -1, -1, -1, -1, 62, -1, -1, -1, 63, 52, 53, 54, 55, 56, 57, 58, 59,
12 60, 61, -1, -1, -1, -1, -1, -1, -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9,
13 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, -1,
14 -1, -1, -1, -1, -1, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37,
15 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, -1, -1, -1,
16 -1, -1 };
17
18 /**
19 * 解密
20 * @param str
21 * @return
22 */
23 public static byte[] decode(String str) {
24 byte[] data = str.getBytes();
25 int len = data.length;
26 ByteArrayOutputStream buf = new ByteArrayOutputStream(len);
27 int i = 0;
28 int b1, b2, b3, b4;
29
30 while (i < len) {
31 do {
32 b1 = base64DecodeChars[data[i++]];
33 } while (i < len && b1 == -1);
34 if (b1 == -1) {
35 break;
36 }
37
38 do {
39 b2 = base64DecodeChars[data[i++]];
40 } while (i < len && b2 == -1);
41 if (b2 == -1) {
42 break;
43 }
44 buf.write((int) ((b1 << 2) | ((b2 & 0x30) >>> 4)));
45
46 do {
47 b3 = data[i++];
48 if (b3 == 61) {
49 return buf.toByteArray();
50 }
51 b3 = base64DecodeChars[b3];
52 } while (i < len && b3 == -1);
53 if (b3 == -1) {
54 break;
55 }
56 buf.write((int) (((b2 & 0x0f) << 4) | ((b3 & 0x3c) >>> 2)));
57
58 do {
59 b4 = data[i++];
60 if (b4 == 61) {
61 return buf.toByteArray();
62 }
63 b4 = base64DecodeChars[b4];
64 } while (i < len && b4 == -1);
65 if (b4 == -1) {
66 break;
67 }
68 buf.write((int) (((b3 & 0x03) << 6) | b4));
69 }
70 return buf.toByteArray();
71 }
72
73
74 System.out.println(new String(decode(username))); // 使用decode()方法进行解密
来源：https://www.cnblogs.com/651434092qq/p/12014608.html