如何使用JavaScript或jQuery对字符串进行SHA-1哈希加密？

嘿，我来帮你搞定用JavaScript（包括配合jQuery）生成SHA-1哈希的问题！其实jQuery本身并没有内置加密功能，核心还是靠JavaScript实现，下面分几种常用场景给你详细讲：

一、现代浏览器推荐：使用原生Web Crypto API #

这是浏览器原生支持的安全加密API，比自己手写的纯JS实现更可靠，不过只支持现代浏览器（Chrome 37+、Firefox 34+、Edge 12+等）。步骤很清晰：

async function sha1Hash(str) {
  // 把字符串转成UTF-8编码的二进制数据
  const encoder = new TextEncoder();
  const data = encoder.encode(str);
  
  // 调用原生API计算SHA-1哈希
  const hashBuffer = await crypto.subtle.digest('SHA-1', data);
  
  // 把二进制结果转成人类可读的十六进制字符串
  const hashArray = Array.from(new Uint8Array(hashBuffer));
  const hashHex = hashArray.map(b => b.toString(16).padStart(2, '0')).join('');
  
  return hashHex;
}

// 调用示例
sha1Hash('Hello World!').then(hash => {
  console.log('SHA-1哈希结果：', hash);
  // 输出：0a0a9f2a6772942557ab5355d76af442f8f65e01
});

二、兼容旧环境：纯JavaScript实现SHA-1 #

如果需要支持IE这类旧浏览器，或者不想依赖Web Crypto，可以用纯JS实现的SHA-1函数。下面是一个经过验证的轻量实现：

function sha1(str) {
  function rotateLeft(n, s) {
    return (n << s) | (n >>> (32 - s));
  }
  
  function toHexString(n) {
    const hexChars = '0123456789abcdef';
    let result = '';
    for (let i = 7; i >= 0; i--) {
      result += hexChars.charAt((n >> (i * 4)) & 0x0F);
    }
    return result;
  }
  
  let blockstart;
  let i, j;
  const W = new Array(80);
  let H0 = 0x67452301;
  let H1 = 0xEFCDAB89;
  let H2 = 0x98BADCFE;
  let H3 = 0x10325476;
  let H4 = 0xC3D2E1F0;
  let A, B, C, D, E;
  let temp;
  
  str = unescape(encodeURIComponent(str));
  const strLen = str.length;
  
  const wordArray = [];
  for (i = 0; i < strLen - 3; i += 4) {
    j = str.charCodeAt(i) << 24 | str.charCodeAt(i + 1) << 16 | str.charCodeAt(i + 2) << 8 | str.charCodeAt(i + 3);
    wordArray.push(j);
  }
  
  switch (strLen % 4) {
    case 0: i = 0x080000000; break;
    case 1: i = str.charCodeAt(strLen - 1) << 24 | 0x0800000; break;
    case 2: i = str.charCodeAt(strLen - 2) << 24 | str.charCodeAt(strLen - 1) << 16 | 0x08000; break;
    case 3: i = str.charCodeAt(strLen - 3) << 24 | str.charCodeAt(strLen - 2) << 16 | str.charCodeAt(strLen - 1) << 8 | 0x80; break;
  }
  
  wordArray.push(i);
  while ((wordArray.length % 16) !== 14) wordArray.push(0);
  wordArray.push(strLen >>> 29);
  wordArray.push((strLen << 3) & 0x0FFFFFFFF);
  
  for (blockstart = 0; blockstart < wordArray.length; blockstart += 16) {
    for (i = 0; i < 16; i++) W[i] = wordArray[blockstart + i];
    for (i = 16; i < 80; i++) W[i] = rotateLeft(W[i - 3] ^ W[i - 8] ^ W[i - 14] ^ W[i - 16], 1);
    
    A = H0; B = H1; C = H2; D = H3; E = H4;
    
    for (i = 0; i < 20; i++) {
      temp = (rotateLeft(A, 5) + ((B & C) | (~B & D)) + E + W[i] + 0x5A827999) & 0x0FFFFFFFF;
      E = D; D = C; C = rotateLeft(B, 30); B = A; A = temp;
    }
    for (i = 20; i < 40; i++) {
      temp = (rotateLeft(A, 5) + (B ^ C ^ D) + E + W[i] + 0x6ED9EBA1) & 0x0FFFFFFFF;
      E = D; D = C; C = rotateLeft(B, 30); B = A; A = temp;
    }
    for (i = 40; i < 60; i++) {
      temp = (rotateLeft(A, 5) + ((B & C) | (B & D) | (C & D)) + E + W[i] + 0x8F1BBCDC) & 0x0FFFFFFFF;
      E = D; D = C; C = rotateLeft(B, 30); B = A; A = temp;
    }
    for (i = 60; i < 80; i++) {
      temp = (rotateLeft(A, 5) + (B ^ C ^ D) + E + W[i] + 0xCA62C1D6) & 0x0FFFFFFFF;
      E = D; D = C; C = rotateLeft(B, 30); B = A; A = temp;
    }
    
    H0 = (H0 + A) & 0x0FFFFFFFF;
    H1 = (H1 + B) & 0x0FFFFFFFF;
    H2 = (H2 + C) & 0x0FFFFFFFF;
    H3 = (H3 + D) & 0x0FFFFFFFF;
    H4 = (H4 + E) & 0x0FFFFFFFF;
  }
  
  return toHexString(H0) + toHexString(H1) + toHexString(H2) + toHexString(H3) + toHexString(H4);
}

// 调用示例
console.log('SHA-1哈希结果：', sha1('Hello World!'));
// 同样输出：0a0a9f2a6772942557ab5355d76af442f8f65e01

三、配合jQuery使用 #

jQuery本身不提供加密能力，但可以用它快速获取页面上的字符串（比如输入框内容），再传给上面的哈希函数：

<input type="text" id="inputStr" placeholder="输入要哈希的字符串">
<button id="hashBtn">生成SHA-1哈希</button>
<div id="result"></div>

<script src="https://code.jquery.com/jquery-3.6.0.min.js"></script>
<script>
// 复用前面的sha1Hash函数
async function sha1Hash(str) { /* ... */ }

$(document).ready(function() {
  $('#hashBtn').click(async function() {
    const input = $('#inputStr').val();
    if (!input) {
      $('#result').text('请输入字符串！');
      return;
    }
    const hash = await sha1Hash(input);
    $('#result').text(`SHA-1哈希：${hash}`);
  });
});
</script>

最后提醒一句：SHA-1现在已经被认为是不安全的加密算法，如果是用于密码存储、数据校验等安全场景，建议使用SHA-256或更安全的算法——上面的Web Crypto API只需要把'SHA-1'改成'SHA-256'就能直接用哦！

内容的提问来源于stack exchange，提问作者Ankit Tyagi