用javascript自己寫一個(gè)進(jìn)制轉(zhuǎn)換小工具

fobnn 發(fā)布于2019-08-23 18:06 / 3193人閱讀

摘要：進(jìn)制轉(zhuǎn)換本身自帶進(jìn)制轉(zhuǎn)換功能，支持進(jìn)制的轉(zhuǎn)換注意，不能直接使用因?yàn)閿?shù)字后面小數(shù)點(diǎn)后面會(huì)被識(shí)別成小數(shù)點(diǎn)的點(diǎn)將十進(jìn)制的轉(zhuǎn)換成進(jìn)制，結(jié)果是將進(jìn)制的轉(zhuǎn)換成進(jìn)制，結(jié)果是將十進(jìn)制的轉(zhuǎn)換成進(jìn)制，結(jié)果是將進(jìn)制的轉(zhuǎn)換成進(jìn)制，結(jié)果是將十進(jìn)制的轉(zhuǎn)換成進(jìn)制，結(jié)果

JavaScript進(jìn)制轉(zhuǎn)換 JavaScript本身自帶進(jìn)制轉(zhuǎn)換功能，支持2-36進(jìn)制的轉(zhuǎn)換

// 注意，不能直接使用 11.toString(16); 因?yàn)閿?shù)字后面小數(shù)點(diǎn)后面會(huì)被識(shí)別成小數(shù)點(diǎn)的點(diǎn)
Number(11).toString(16); // 將十進(jìn)制的11轉(zhuǎn)換成16進(jìn)制，結(jié)果是b
parseInt("b", 16); // 將16進(jìn)制的b轉(zhuǎn)換成10進(jìn)制，結(jié)果是11

Number(38).toString(36); // 將十進(jìn)制的38轉(zhuǎn)換成36進(jìn)制，結(jié)果是12
parseInt(12, 36); // 將36進(jìn)制的12轉(zhuǎn)換成10進(jìn)制，結(jié)果是38

Number(27).toString(2); // 將十進(jìn)制的27轉(zhuǎn)換成2進(jìn)制，結(jié)果是11011
parseInt("11011", 2); 、// 將二進(jìn)制的11011轉(zhuǎn)換成10進(jìn)制，結(jié)果是27

但是如果要寫超過(guò)36進(jìn)制的進(jìn)制轉(zhuǎn)換，js就不支持了 自己寫了一個(gè)進(jìn)制轉(zhuǎn)換工具，可自定義字符對(duì)應(yīng)關(guān)系

/**
 * 十進(jìn)制和其他進(jìn)制的相互轉(zhuǎn)換
 */
class MyNumberConvertion {
    constructor(chars) {
        this.chars = chars;
        this.RADIX = chars.length;
        this.map = new Map();
        for (let i = 0; i < this.RADIX; i++) {
            let c = chars[i];
            this.map.set(c, i);
        }
    }

    /**
     * 將十進(jìn)制數(shù)字轉(zhuǎn)換成指定進(jìn)制
     * @param {Number, String} num 
     */
    transfer(num) {
        let a = +num; //把字符串變成數(shù)字
        let arr = [];
        if (a === 0) {
            arr.push("0");
        }
        const RADIX = this.RADIX;
        while (a > 0) {
            let tmp = a % RADIX;
            let c = this.chars[tmp];
            arr.unshift(c);
            a = parseInt(a / RADIX);
        }
        return arr.join("");
    }

    /**
     * 將字符串還原成指定進(jìn)制
     * @param {String} str 
     */
    revert(str) {
        str = str + "";
        str = str.trim();
        let num = 0;
        let len = str.length;
        let RADIX = this.RADIX;
        for (let i = 0; i < len; i++) {
            let s = str[i];
            let a = this.map.get(str[i]);
            num += a * Math.pow(RADIX, len - i - 1);
        }
        return num;
    }
}

示例如下：

console.log("64進(jìn)制");
// //初始化的字符串，字符串長(zhǎng)度就是進(jìn)制，從左到右，0對(duì)應(yīng)數(shù)值0，最后一個(gè)字符~對(duì)應(yīng)數(shù)值63
const chars64 = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ-~";
// //初始化轉(zhuǎn)換器
const convertion64 = new MyNumberConvertion(chars64);
let str64 = "445306828";
let num64 = convertion64.transfer(str64);//將數(shù)字轉(zhuǎn)換成64進(jìn)制
let source64 = convertion64.revert(num64);//將64進(jìn)制字符還原成原始數(shù)據(jù)
console.log(`原始數(shù)據(jù)：${str64}`);
console.log(`轉(zhuǎn)換后：${num64}`)
console.log(`還原后：${source64}`);

console.log("2進(jìn)制");
const convertion2 = new MyNumberConvertion("01");
let str2 = 15;
let num2 = convertion2.transfer(str2);
let source2 = convertion2.revert(num2);
console.log(`原始數(shù)據(jù)：${str2}`);
console.log(`轉(zhuǎn)換后：${num2}`)
console.log(`還原后：${source2}`);

console.log("8進(jìn)制");
const convertion8 = new MyNumberConvertion("01234567");
let str8 = 39;
let num8 = convertion8.transfer(str8);
let source8 = convertion8.revert(num8);
console.log(`原始數(shù)據(jù)：${str8}`);
console.log(`轉(zhuǎn)換后：${num8}`)
console.log(`還原后：${source8}`);

進(jìn)制轉(zhuǎn)換小工具