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?
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)
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);
}
}
var大小=[“字节”,“知识库”,“m”,“g”,“结核”,“铅”、“海尔哥哥”,“ZB”,“YB”);
函数formatBytes(字节,小数){
For (var I = 0, r = bytes, b = 1024;R > b;I ++) r /= b;
返回' ${parseFloat(r.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];
}
}