我只是晚了10年!对于es6

function humanReadableSize(bytes) {
    let size = parseInt(data)
    for (let unit of ['b', 'Kb', 'Mb', 'Gb']) {
        if (size < 1024) return `${size.toFixed(2)} ${unit}`
        size /= 1024.0
    }
}

这是我写的一个:

/** * Format bytes as human-readable text. * * @param bytes Number of bytes. * @param si True to use metric (SI) units, aka powers of 1000. False to use * binary (IEC), aka powers of 1024. * @param dp Number of decimal places to display. * * @return Formatted string. */ function humanFileSize(bytes, si=false, dp=1) { const thresh = si ? 1000 : 1024; if (Math.abs(bytes) < thresh) { return bytes + ' B'; } const units = si ? ['kB', 'MB', 'GB', 'TB', 'PB', 'EB', 'ZB', 'YB'] : ['KiB', 'MiB', 'GiB', 'TiB', 'PiB', 'EiB', 'ZiB', 'YiB']; let u = -1; const r = 10**dp; do { bytes /= thresh; ++u; } while (Math.round(Math.abs(bytes) * r) / r >= thresh && u < units.length - 1); return bytes.toFixed(dp) + ' ' + units[u]; } console.log(humanFileSize(1551859712)) // 1.4 GiB console.log(humanFileSize(5000, true)) // 5.0 kB console.log(humanFileSize(5000, false)) // 4.9 KiB console.log(humanFileSize(-10000000000000000000000000000)) // -8271.8 YiB console.log(humanFileSize(999949, true)) // 999.9 kB console.log(humanFileSize(999950, true)) // 1.0 MB console.log(humanFileSize(999950, true, 2)) // 999.95 kB console.log(humanFileSize(999500, true, 0)) // 1 MB

基于cocco的答案，但略有淡化(老实说，那些我觉得舒服的被保留/添加)，不显示后面的0，但仍然支持0，希望对其他人有用:

函数fileSizeSI(size) { var e = (Math.log(size) / Math.log(1e3)) | 0; return +(size / Math.)战俘(1 e3, e)) .toFixed (2 ) + ' ' + (' kMGTPEZY [e - 1 ] || '') + ' B”; ｝ / /测试: 文档。write([0, 23, 4322, 324232132, 22e9, 64.22e12, 76.22e15, 64.66e18, 77.11e21, 22e24].map(fileSizeSI).join('<br>'));

@Andrew V的typescript版本带有新的“模板文字类型”

export const humanFileSize = (bytes: number): `${number} ${'B' | 'KB' | 'MB' | 'GB' | 'TB'}` => {
    const index = Math.floor(Math.log(bytes) / Math.log(1024));
    return `${Number((bytes / Math.pow(1024, index)).toFixed(2)) * 1} ${(['B', 'KB', 'MB', 'GB', 'TB'] as const)[index]}`;
};

这是笔答题尺寸的改进

function humanFileSize(bytes, si=false) {
  let u, b=bytes, t= si ? 1000 : 1024;     
  ['', si?'k':'K', ...'MGTPEZY'].find(x=> (u=x, b/=t, b**2<1));
  return `${u ? (t*b).toFixed(1) : bytes} ${u}${!si && u ? 'i':''}B`;    
}

函数humanFileSize(bytes, si=false) { 设u, b=bytes, t= si ?1000: 1024; [",如果?“k”:“k”,…' MGTPEZY ']。Find (x=> (u=x, b/=t, b**2<1)); 返回' ${u ?(t*b).toFixed(1): bytes} ${u}${!Si && u ?“我”:“B} '; ｝ / /测试 console.log (humanFileSize (5000));// 4.9 KiB . console.log (humanFileSize(5000,真的));// 5.0 kB

我发现@cocco的回答很有趣，但有以下问题:

不要修改原生类型或您不拥有的类型 为人类编写干净、可读的代码，让最小化器为机器优化代码 (对TypeScript用户的奖励)不能很好地使用TypeScript

打字稿:

 /**
 * Describes manner by which a quantity of bytes will be formatted.
 */
enum ByteFormat {
  /**
   * Use Base 10 (1 kB = 1000 bytes). Recommended for sizes of files on disk, disk sizes, bandwidth.
   */
  SI = 0,
  /**
   * Use Base 2 (1 KiB = 1024 bytes). Recommended for RAM size, size of files on disk.
   */
  IEC = 1
}

/**
 * Returns a human-readable representation of a quantity of bytes in the most reasonable unit of magnitude.
 * @example
 * formatBytes(0) // returns "0 bytes"
 * formatBytes(1) // returns "1 byte"
 * formatBytes(1024, ByteFormat.IEC) // returns "1 KiB"
 * formatBytes(1024, ByteFormat.SI) // returns "1.02 kB"
 * @param size The size in bytes.
 * @param format Format using SI (Base 10) or IEC (Base 2). Defaults to SI.
 * @returns A string describing the bytes in the most reasonable unit of magnitude.
 */
function formatBytes(
  value: number,
  format: ByteFormat = ByteFormat.SI
) {
  const [multiple, k, suffix] = (format === ByteFormat.SI
    ? [1000, 'k', 'B']
    : [1024, 'K', 'iB']) as [number, string, string]
  // tslint:disable-next-line: no-bitwise
  const exp = (Math.log(value) / Math.log(multiple)) | 0
  // or, if you'd prefer not to use bitwise expressions or disabling tslint rules, remove the line above and use the following:
  // const exp = value === 0 ? 0 : Math.floor(Math.log(value) / Math.log(multiple)) 
  const size = Number((value / Math.pow(multiple, exp)).toFixed(2))
  return (
    size +
    ' ' +
    (exp 
       ? (k + 'MGTPEZY')[exp - 1] + suffix 
       : 'byte' + (size !== 1 ? 's' : ''))
  )
}

// example
[0, 1, 1024, Math.pow(1024, 2), Math.floor(Math.pow(1024, 2) * 2.34), Math.pow(1024, 3), Math.floor(Math.pow(1024, 3) * 892.2)].forEach(size => {
  console.log('Bytes: ' + size)
  console.log('SI size: ' + formatBytes(size))
  console.log('IEC size: ' + formatBytes(size, 1) + '\n')
});