JS裏charCodeAt()和fromCharCode()方法拓展應用:加密與解密

JS實現客戶端的網頁加密解密技術,可用做選擇性隱蔽展現。固然客戶端的加密安全度是不能與服務器相提並論,確定不能用於密碼這類內容的加密,但對於通常級別的內容用做展現已經夠了。html

JS加密與解密的解決方案有不少,本文則利用String對象的charCodeAt()方法和fromCharCode()方法對字符的ASCII編碼進行獲取和修改。安全

加密,解密代碼:服務器

 1 <!DOCTYPE html>
 2 <html>
 3 <head>
 4     <meta charset="utf-8">
 5 
 6     <title>網頁加密及解密</title>
 7     <meta name="author" content="xiongzaiqiren" />
 8     <meta name="keywords" content="" />
 9     <meta name="description" content="" />
10     <meta name="generator" content="ClassBao team coding in July 10, 2017" />
11 
12 </head>
13 
14 <body>
15     <p><textarea id="text1" name="textfield" cols="50" rows="5">錢莊王員外這我的怎麼樣?</textarea></p>
16     <input type="button" name="Button1" value="加密" onClick="text1.value = MySign.Encrypt(text1.value);">
17     <input type="button" name="Button2" value="解密" onClick="text1.value = MySign.UnEncrypt(text1.value);">
18 
19     <script language="JavaScript">
20         var MySign = {
21             //加密/解密次數
22             num: 0,
23             //加密
24             Encrypt: function (Text) {
25                 this.num = this.num + 1;
26                 output = new String;
27                 alterText = new Array();
28                 varCost = new Array();
29                 TextSize = Text.length;
30                 for (i = 0; i < TextSize; i++) {
31                     idea = Math.round(Math.random() * 111) + 77;
32                     alterText[i] = Text.charCodeAt(i) + idea;
33                     varCost[i] = idea;
34                 }
35                 for (i = 0; i < TextSize; i++) {
36                     output += String.fromCharCode(alterText[i], varCost[i]);
37                 }
38                 //text1.value = output;
39                 return output;
40             },
41 
42             //解密
43             UnEncrypt: function (Text) {
44                 if (this.num > 0) {
45                     this.num = this.num - 1;
46                     output = new String;
47                     alterText1 = new Array();
48                     varCost1 = new Array();
49                     TextSize = Text.length;
50                     for (i = 0; i < TextSize; i++) {
51                         alterText[i] = Text.charCodeAt(i);
52                         varCost[i] = Text.charCodeAt(i + 1);
53                     }
54                     for (i = 0; i < TextSize; i = i + 2) {
55                         output += String.fromCharCode(alterText[i] - varCost[i]);
56                     }
57                     //text1.value = output;
58                     return output;
59                 }
60             }
61         };
62 
63 
64         //測試代碼
65         var testString = "光頭強,還不去砍樹?";
66         console.log(testString);
67 
68         var sign = MySign.Encrypt(testString); //湊ˆ妣o忕›ァ[還¬什³呯´硠S桲aチb
69         var sign2 = MySign.UnEncrypt(sign); //光頭強,還不去砍樹?
70 
71         console.log(sign);
72         console.log(sign2);
73 
74     </script>
75 
76 </body>
77 </html>