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?
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))} ${SIZES[i]} ';
}
const byteConversion = (bytes: number, decimals = 2) => {
if (bytes === 0) return '0 B';
const kiloByte = 1000;
const decimal = decimals < 0 ? 0 : decimals;
const sizes = ['B', 'KB', 'MB', 'GB', 'TB', 'PB', 'EB', 'ZB', 'YB'];
const i: number = Math.floor(Math.log(bytes) / Math.log(kiloByte));
return `${parseFloat((bytes / kiloByte ** i).toFixed(decimal))} ${sizes[i]}`;
};
这里有一句话:
val => ['Bytes','Kb','Mb','Gb','Tb'][Math.floor(Math.log2(val)/10)]
甚至:
v => 'BKMGT'[~~(Math.log2(v)/10)]
与数:
function shortenBytes(n) {
const k = n > 0 ? Math.floor((Math.log2(n)/10)) : 0;
const rank = (k > 0 ? 'KMGT'[k - 1] : '') + 'b';
const count = Math.floor(n / Math.pow(1024, k));
return count + rank;
}
我让算法快了7倍(就像忍者一样):
function rafaelFormatBytes(number){
if(number == null || number === undefined || number <= 0) {
return '0 Bytes';
}
var scaleCounter = 0;
var scaleInitials = [' Bytes',' KB',' MB',' GB',' TB',' PB',' EB',' ZB',' YB'];
while (number >= 1024 && scaleCounter < scaleInitials.length - 1){
number /= 1024;
scaleCounter++;
}
if(scaleCounter >= scaleInitials.length) scaleCounter = scaleInitials.length - 1;
var compactNumber = number.toFixed(2)
.replace(/\.?0+$/,'')
.replace(/\B(?=(\d{3})+(?!\d))/g, ",");
compactNumber += scaleInitials[scaleCounter];
return compactNumber.trim();
}
var testNum = 0;
var startTime, endTime;
function start() {
startTime = new Date();
};
function end() {
endTime = new Date();
var timeDiff = endTime - startTime; //in ms
// strip the ms
timeDiff /= 1000;
// get seconds
var seconds = Math.round(timeDiff, 5);
console.log(timeDiff + " seconds");
}
function formatBytes(a,b=2,k=1024){with(Math){let d=floor(log(a)/log(k));return 0==a?"0 Bytes":parseFloat((a/pow(k,d)).toFixed(max(0,b)))+" "+["Bytes","KB","MB","GB","TB","PB","EB","ZB","YB"][d]}}
console.log(formatBytes(1000000000000000000000000000));
console.log(rafaelFormatBytes(1000000000000000000000000000));
start();
for(i=0; i<100000; i++){
formatBytes(1000000000000000);
}
end();
start();
for(i=0; i<100000; i++){
rafaelFormatBytes(1000000000000000);
}
end();
... 输出:
827.18 YB
827.18 YB
0.293 seconds
0.039 seconds
耶稣基督!