JavaScript 代码段

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数字转换

  • 十进制和16进制相互转换

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    let hexNumber = (n).toString(16); // to hex
    let decimal = parseInt(hexNumber, 16); // to decimal

  • 16进制字符串转换为ACSII

From: Stack Overflow

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function hex2a(data) {
    let hex = data.toString();
    let str = '';
    for(let i = 0; i < hex.length; i += 2) {
        str += String.fromCharCode(parseInt(hex.substr(i, 2), 16));
    }

    return str;
}

加密

  • sha1 加密
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    var crypto = require('crypto');
    var sha1 = crypto.createHash('sha1');
    sha1.update('str').digest('hex');

其它

  • padLeft

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    // ES6

    function padLeft(str, len) {
        let val = '0'.repeat(len - str.length) + str;

        return val;
     }

  • reverse

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    function reverse(str) {
        return str.split('').reverse().join('');
    }