我正在制作一个自制文本加密器并且工作正常 - 除了有时它会错误地解密邮件这一事实。请参阅代码示例（抱歉，它非常混乱，我只是从HTML / JS开始）：
要看到它出错，请输入＆＃39; hi＆＃39;作为消息和＆＃39; moo123＆＃39;作为关键。不要问为什么，当我发现问题时，我只是在尝试随机的话。然后使用相同的密钥将加密的消息复制到文本输入中，然后按解密。它说'那里'＆＃39;代替。
有人可以告诉我为什么会这样，以及如何解决这个问题？谢谢！
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Encryptor</title>
<style>
body {
font-family: monospace;
}
input {
font-family: monospace;
width: 400px;
}
</style>
</head>
<body>
<h1>Encryptor</h1>
<p>Enter the text to encrypt:</p>
<input type="text" id="text">
<p>Enter the encrytion key:</p>
<input type="text" id="key"><br><br>
<button onclick="encrypt()">Encrypt</button>
<button onclick="decrypt()">Decrypt</button><br><br>
<p id="output"></p>
<p id="debug"></p>
<script>
function encrypt() {
//console.log("----------------");
var text = document.getElementById("text").value;
var key = document.getElementById("key").value;
var chars = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789!£$%^&_={}:;@'~#<,>./|`¬ abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789!£$%^&-={}:;@'~#<,>./|`¬ abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789!£$%^&-={}:;@'~#<,>./|`¬ ";
//var chars = "abcdefghijklmnopqrstuvwxyz"
var output = "";
var keyNum = 0;
var char = "";
var keychar = "";
var finalchar = "";
for (var i = 0; i < text.length; i++) {
char = chars.search((text.substring(i, i+1)))+87;
//console.log("char "+char);
//keychar = chars.search(key.substring(keyNum, KeyNum+1));
//document.getElementById("output").innerHTML = key.substring(keyNum, keyNum+1);
keychar = (chars.search(key.substring(keyNum, keyNum+1)));
//console.log("keychar "+keychar);
//console.log("char - keychar "+parseFloat(char)-parseFloat(keychar));
finalchar = chars[parseFloat(char)-parseFloat(keychar)];
output = output + finalchar;
if (keyNum >= key.length-1) {
keyNum = 0;
} else {
keyNum++;
}
}
document.getElementById("output").innerHTML = output;
}
function decrypt() {
//console.log("----------------");
var text = document.getElementById("text").value;
var key = document.getElementById("key").value;
var chars = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789!£$%^&_={}:;@'~#<,>./|`¬ abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789!£$%^&_={}:;@'~#<,>./|`¬ abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789!£$%^&_={}:;@'~#<,>./|`¬ ";
//var chars = "abcdefghijklmnopqrstuvwxyz"
var output = "";
var keyNum = 0;
var char = "";
var keychar = "";
var finalchar = "";
for (var i = 0; i < text.length; i++) {
char = chars.search((text.substring(i, i+1)));
//console.log("char "+char);
//keychar = chars.search(key.substring(keyNum, KeyNum+1));
//document.getElementById("output").innerHTML = key.substring(keyNum, keyNum+1);
keychar = (chars.search(key.substring(keyNum, keyNum+1)))+87;
//console.log("keychar "+keychar);
//console.log("char - keychar "+parseFloat(char)-parseFloat(keychar));
finalchar = chars[parseFloat(char)+parseFloat(keychar)];
output = output + finalchar;
if (keyNum >= key.length-1) {
keyNum = 0;
} else {
keyNum++;
}
}
document.getElementById("output").innerHTML = output;
}
</script>
</body>
</html>
答案 0 :(得分：0)
您正在使用string.prototype.search assumes a regular expression as input。由于这个原因，字符串中的某些字符无法正常工作。例如，如果您加密hi，它将返回/.，但.是＆＃34;任何字符＆＃34;所以它将返回0作为匹配。请改用indexOf。
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Encryptor</title>
<style>
body {
font-family: monospace;
}
input {
font-family: monospace;
width: 400px;
}
</style>
</head>
<body>
<h1>Encryptor</h1>
<p>Enter the text to encrypt:</p>
<input type="text" id="text">
<p>Enter the encrytion key:</p>
<input type="text" id="key"><br><br>
<button onclick="encrypt()">Encrypt</button>
<button onclick="decrypt()">Decrypt</button><br><br>
<p id="output"></p>
<p id="debug"></p>
<script>
function encrypt() {
//console.log("----------------");
var text = document.getElementById("text").value;
var key = document.getElementById("key").value;
var chars = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789!£$%^&_={}:;@'~#<,>./|`¬ abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789!£$%^&_={}:;@'~#<,>./|`¬ abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789!£$%^&_={}:;@'~#<,>./|`¬ ";
//var chars = "abcdefghijklmnopqrstuvwxyz"
var output = "";
var keyNum = 0;
var char = "";
var keychar = "";
var finalchar = "";
for (var i = 0; i < text.length; i++) {
char = chars.indexOf((text.substring(i, i+1)))+87;
//console.log("char "+char);
//keychar = chars.search(key.substring(keyNum, KeyNum+1));
//document.getElementById("output").innerHTML = key.substring(keyNum, keyNum+1);
keychar = (chars.indexOf(key.substring(keyNum, keyNum+1)));
//console.log("keychar "+keychar);
//console.log("char - keychar "+parseFloat(char)-parseFloat(keychar));
finalchar = chars[parseFloat(char)-parseFloat(keychar)];
output = output + finalchar;
if (keyNum >= key.length-1) {
keyNum = 0;
} else {
keyNum++;
}
}
document.getElementById("output").innerHTML = output;
}
function decrypt() {
//console.log("----------------");
var text = document.getElementById("text").value;
var key = document.getElementById("key").value;
var chars = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789!£$%^&_={}:;@'~#<,>./|`¬ abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789!£$%^&_={}:;@'~#<,>./|`¬ abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789!£$%^&_={}:;@'~#<,>./|`¬ ";
//var chars = "abcdefghijklmnopqrstuvwxyz"
var output = "";
var keyNum = 0;
var char = "";
var keychar = "";
var finalchar = "";
for (var i = 0; i < text.length; i++) {
char = chars.indexOf((text.substring(i, i+1)));
//console.log("char "+char);
//keychar = chars.search(key.substring(keyNum, KeyNum+1));
//document.getElementById("output").innerHTML = key.substring(keyNum, keyNum+1);
keychar = (chars.indexOf(key.substring(keyNum, keyNum+1)))+87;
//console.log("keychar "+keychar);
//console.log("char - keychar "+parseFloat(char)-parseFloat(keychar));
finalchar = chars[parseFloat(char)+parseFloat(keychar)];
output = output + finalchar;
if (keyNum >= key.length-1) {
keyNum = 0;
} else {
keyNum++;
}
}
document.getElementById("output").innerHTML = output;
}
</script>
</body>
</html>
另外，请注意，如果您仔细比较它们，那么两个char字符串实际上并不相同。这可能也是一个问题，但我不确定它是否是故意的（我假设不是）？ 现已更正