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";
}

这是一个坚实的有效的方法来转换字节。你唯一需要做的就是安装mathjs库进行精确的计算。复制粘贴即可。

import { multiply, divide, round } from "mathjs";

class Size {
  constructor(value, unit) {
    this.value = value;
    this.unit = unit.toUpperCase();
  }
}

async function byteToSize(bytes) {
  const B = 1;
  const KB = multiply(B, 1024);
  const MB = multiply(KB, 1024);
  const GB = multiply(MB, 1024);
  const TB = multiply(GB, 1024);
  const PB = multiply(TB, 1024);

  if (bytes <= KB) {
    // @returns BYTE

    const result = round(divide(bytes, B));
    const unit = `B`;

    return new Size(result, unit);
  }

  if (bytes <= MB) {
    // @returns KILOBYTE

    const result = round(divide(bytes, KB));
    const unit = `KB`;

    return new Size(result, unit);
  }

  if (bytes <= GB) {
    // @returns MEGABYTE

    const result = round(divide(bytes, MB));
    const unit = `MB`;

    return new Size(result, unit);
  }

  if (bytes <= TB) {
    // @returns GIGABYTE

    const result = round(divide(bytes, GB));
    const unit = `GB`;

    return new Size(result, unit);
  }

  if (bytes <= PB) {
    // @returns TERABYTE

    const result = divide(bytes, TB).toFixed(2);
    const unit = `TB`;

    return new Size(result, unit);
  }

  if (bytes >= PB) {
    // @returns PETABYTE

    const result = divide(bytes, PB).toFixed(2);
    const unit = `PB`;

    return new Size(result, unit);
  }
}

更灵活和考虑最大pow尺寸列表 (升级后的l2aelba答案)

function formatBytes(bytes, decimals = 2, isBinary = false) {
      const sizes = ['Bytes', 'KB', 'MB', 'GB', 'TB']; // or ['B', 'KB', 'MB', 'GB', 'TB']
    
      if (!+bytes) {
        return `0 ${sizes[0]}`;
      }
    
      const inByte = isBinary ? 1024 : 1000;
      const dm = decimals < 0 ? 0 : decimals;
    
      const pow = Math.floor(Math.log(bytes) / Math.log(inByte));
      const maxPow = Math.min(pow, sizes.length - 1);
    
      return `${parseFloat((bytes / Math.pow(inByte, maxPow)).toFixed(dm))} ${
        sizes[maxPow]
      }`;
    }

我只是想分享我的想法。我遇到了这个问题，所以我的解决方案是这样的。这将把低单位转换为高单位，反之亦然，只需提供参数toUnit和fromUnit

export function fileSizeConverter(size: number, fromUnit: string, toUnit: string ): number | string {
  const units: string[] = ['B', 'KB', 'MB', 'GB', 'TB'];
  const from = units.indexOf(fromUnit.toUpperCase());
  const to = units.indexOf(toUnit.toUpperCase());
  const BASE_SIZE = 1024;
  let result: number | string = 0;

  if (from < 0 || to < 0 ) { return result = 'Error: Incorrect units'; }

  result = from < to ? size / (BASE_SIZE ** to) : size * (BASE_SIZE ** from);

  return result.toFixed(2);
}

我从这里得到了灵感

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";
}

这对我很有用。

bytesForHuman(bytes) {
    let units = ['B', 'KB', 'MB', 'GB', 'TB', 'PB']

    let i = 0
    
    for (i; bytes > 1024; i++) {
        bytes /= 1024;
    }

    return bytes.toFixed(1) + ' ' + units[i]
}