const byteConversion = (bytes: number, decimals = 2) => {
if (bytes === 0) return '0 B';

const kiloByte = 1000;
const decimal = decimals < 0 ? 0 : decimals;
const sizes = ['B', 'KB', 'MB', 'GB', 'TB', 'PB', 'EB', 'ZB', 'YB'];

const i: number = Math.floor(Math.log(bytes) / Math.log(kiloByte));

return `${parseFloat((bytes / kiloByte ** i).toFixed(decimal))} ${sizes[i]}`;

};

当与字节相关时，有两种真实的方法来表示大小，它们是SI单位(10^3)或IEC单位(2^10)。也有JEDEC，但他们的方法是模糊的和令人困惑的。我注意到其他示例有错误，例如使用KB而不是KB来表示千字节，因此我决定编写一个函数，使用当前接受的度量单位的范围来解决这些情况。

在结尾有一个格式化的地方，这将使数字看起来更好一点(至少在我看来)，如果它不适合你的目的，请随意删除这个格式。

享受。

// pBytes: the size in bytes to be converted.
// pUnits: 'si'|'iec' si units means the order of magnitude is 10^3, iec uses 2^10

function prettyNumber(pBytes, pUnits) {
    // Handle some special cases
    if(pBytes == 0) return '0 Bytes';
    if(pBytes == 1) return '1 Byte';
    if(pBytes == -1) return '-1 Byte';

    var bytes = Math.abs(pBytes)
    if(pUnits && pUnits.toLowerCase() && pUnits.toLowerCase() == 'si') {
        // SI units use the Metric representation based on 10^3 as a order of magnitude
        var orderOfMagnitude = Math.pow(10, 3);
        var abbreviations = ['Bytes', 'kB', 'MB', 'GB', 'TB', 'PB', 'EB', 'ZB', 'YB'];
    } else {
        // IEC units use 2^10 as an order of magnitude
        var orderOfMagnitude = Math.pow(2, 10);
        var abbreviations = ['Bytes', 'KiB', 'MiB', 'GiB', 'TiB', 'PiB', 'EiB', 'ZiB', 'YiB'];
    }
    var i = Math.floor(Math.log(bytes) / Math.log(orderOfMagnitude));
    var result = (bytes / Math.pow(orderOfMagnitude, i));

    // This will get the sign right
    if(pBytes < 0) {
        result *= -1;
    }

    // This bit here is purely for show. it drops the percision on numbers greater than 100 before the units.
    // it also always shows the full number of bytes if bytes is the unit.
    if(result >= 99.995 || i==0) {
        return result.toFixed(0) + ' ' + abbreviations[i];
    } else {
        return result.toFixed(2) + ' ' + abbreviations[i];
    }
}

function formatBytes(bytes) {
    var marker = 1024; // Change to 1000 if required
    var decimal = 3; // Change as required
    var kiloBytes = marker; // One Kilobyte is 1024 bytes
    var megaBytes = marker * marker; // One MB is 1024 KB
    var gigaBytes = marker * marker * marker; // One GB is 1024 MB
    var teraBytes = marker * marker * marker * marker; // One TB is 1024 GB

    // return bytes if less than a KB
    if(bytes < kiloBytes) return bytes + " Bytes";
    // return KB if less than a MB
    else if(bytes < megaBytes) return(bytes / kiloBytes).toFixed(decimal) + " KB";
    // return MB if less than a GB
    else if(bytes < gigaBytes) return(bytes / megaBytes).toFixed(decimal) + " MB";
    // return GB if less than a TB
    else return(bytes / gigaBytes).toFixed(decimal) + " GB";
}

将字节格式化为最符合逻辑大小(KB、MB或GB)的实用程序方法。

Number.prototype.formatBytes = function() { var单位= ['B'， 'KB'， 'MB'， 'GB'， 'TB']， 字节= this， 我; For (i = 0;>= 1024 && I < 4;我+ +){ 字节/= 1024; ｝ return bytes.toFixed(2) + units[i]; ｝ 令a = 235678;/ /字节 console.log (a.formatBytes ());//结果为230.15KB

这是一个字节应该如何显示给人类:

function bytesToHuman(bytes, decimals = 2) {
  // https://en.wikipedia.org/wiki/Orders_of_magnitude_(data)
  const units = ["bytes", "KiB", "MiB", "GiB", "TiB", "PiB", "EiB"]; // etc

  let i = 0;
  let h = 0;

  let c = 1 / 1023; // change it to 1024 and see the diff

  for (; h < c && i < units.length; i++) {
    if ((h = Math.pow(1024, i) / bytes) >= c) {
      break;
    }
  }

  // remove toFixed and let `locale` controls formatting
  return (1 / h).toFixed(decimals).toLocaleString() + " " + units[i];
}

// test
for (let i = 0; i < 9; i++) {
  let val = i * Math.pow(10, i);
  console.log(val.toLocaleString() + " bytes is the same as " + bytesToHuman(val));

}

// let's fool around
console.log(bytesToHuman(1023));
console.log(bytesToHuman(1024));
console.log(bytesToHuman(1025));

你可以使用pretty-bytes库。

安装

npm install pretty-bytes

使用

import prettyBytes from 'pretty-bytes';

prettyBytes(1337);
//=> '1.34 kB'

prettyBytes(100);
//=> '100 B'

// Display with units of bits
prettyBytes(1337, {bits: true});
//=> '1.34 kbit'

// Display file size differences
prettyBytes(42, {signed: true});
//=> '+42 B'

// Localized output using German locale
prettyBytes(1337, {locale: 'de'});
//=> '1,34 kB'