我得到这段代码通过PHP隐蔽大小字节。

现在我想使用JavaScript将这些大小转换为人类可读的大小。我尝试将这段代码转换为JavaScript,看起来像这样:

function formatSizeUnits(bytes){
  if      (bytes >= 1073741824) { bytes = (bytes / 1073741824).toFixed(2) + " GB"; }
  else if (bytes >= 1048576)    { bytes = (bytes / 1048576).toFixed(2) + " MB"; }
  else if (bytes >= 1024)       { bytes = (bytes / 1024).toFixed(2) + " KB"; }
  else if (bytes > 1)           { bytes = bytes + " bytes"; }
  else if (bytes == 1)          { bytes = bytes + " byte"; }
  else                          { bytes = "0 bytes"; }
  return bytes;
}

这是正确的做法吗?有没有更简单的方法?


当前回答

由此可见:(来源)


Unminified and es6’ed:(社区)

function formatBytes(bytes, decimals = 2) { if (!+bytes) return '0 Bytes' const k = 1024 const dm = decimals < 0 ? 0 : decimals const sizes = ['Bytes', 'KB', 'MB', 'GB', 'TB', 'PB', 'EB', 'ZB', 'YB'] const i = Math.floor(Math.log(bytes) / Math.log(k)) return `${parseFloat((bytes / Math.pow(k, i)).toFixed(dm))} ${sizes[i]}` } // Demo code document.body.innerHTML += `<input type="text" oninput="document.querySelector('p').innerHTML=formatBytes(this.value)" value="1000"><p>1000 Bytes</p>`

简化版(由StackOverflow社区提供,由JSCompress提供)

function formatBytes(a,b=2){if(!+a)return"0 Bytes";const c=0>b?0:b,d=Math.floor(Math.log(a)/Math.log(1024));return`${parseFloat((a/Math.pow(1024,d)).toFixed(c))} ${["Bytes","KB","MB","GB","TB","PB","EB","ZB","YB"][d]}`}

用法:

// formatBytes(bytes, decimals)

formatBytes(1024)       // 1 KB
formatBytes('1024')     // 1 KB
formatBytes(1234)       // 1.21 KB
formatBytes(1234, 3)    // 1.205 KB
formatBytes(0)          // 0 Bytes
formatBytes('0')        // 0 Bytes

PS:更改k = 1000或大小=["…如你所愿(比特或字节)

其他回答

我使用递归和分配水平变量为适当的单位。

函数getReadableByte(count, decimal=0, level=0) { 让unitList =[“字节”,“知识库”,“m”,“g”、“肺结核”,“PT”); if (count >= 1024.0 && (level+1 < unitList.length)) { 返回getReadableByte(count/1024, decimal, ++level) } 返回' ${小数?(count).toFixed(decimal): Math.round(count)}${unitList[level]} ' } 2) console.log (getReadableByte (120)

我正在更新@ al冰岛的答案。由于小数点对于1,2位数的数字很重要,所以我舍入了第一个小数点并保留第一个小数点。对于3位数的数字,我舍入个位数,忽略所有小数点后的位置。

getMultiplers : function(bytes){
    var unit = 1000 ;
    if (bytes < unit) return bytes ;
    var exp = Math.floor(Math.log(bytes) / Math.log(unit));
    var pre = "kMGTPE".charAt(exp-1);
    var result = bytes / Math.pow(unit, exp);
    if(result/100 < 1)
        return (Math.round( result * 10 ) / 10) +pre;
    else
        return Math.round(result) + pre;
}

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);
  }
}

一行程序

const b2s = t = > {let’e = Math .对数(t) / 10 | 0; return (t / 1024 * * (e = e < = 0 ? 0 toFixed: e))(3) +“BKMGP”[e]}; console . log (b2s (0)); console . log (b2s (123)); console . log (b2s (123123)); console . log (b2s (123123123)); console . log (b2s (123123123123)); console . log (b2s (123123123123123));

@ al冰岛jm也给出了同样的答案,但以一种“更说教”的方式。谢谢!= D

function formatBytes(numBytes, decPlaces) {
    /* Adjust the number of bytes informed for the most appropriate metric according
    to its value.

    Args:
        numBytes (number): The number of bytes (integer);
        decPlaces (Optional[number])): The number of decimal places (integer). If
            it is "undefined" the value "2" will be adopted.

    Returns:
        string: The number adjusted together with the most appropriate metric. */

    if (numBytes === 0) {
        return "0 Bytes";
    }

    // NOTE: 1 KB is equal to 1024 Bytes. By Questor
    // [Ref(s).: https://en.wikipedia.org/wiki/Kilobyte ]
    var oneKByte = 1024;

    // NOTE: Treats if the "decPlaces" is "undefined". If it is "undefined" the value
    // "2" will be adopted. By Questor
    if (decPlaces === undefined || decPlaces === "") {
        decPlaces = 2;
    }

    var byteMtrcs = ["Bytes", "KB", "MB", "GB", "TB", "PB", "EB", "ZB", "YB"];
    // Byte Metrics

    // NOTE: Defines the factor for the number of bytes and the metric. By Questor
    var mtrcNumbFactor = Math.floor(Math.log(numBytes) / Math.log(oneKByte));
    // Metrics Number Factor

    return parseFloat((numBytes / Math.pow(oneKByte, mtrcNumbFactor)).
            toFixed(decPlaces)) + " " + byteMtrcs[mtrcNumbFactor];
}