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?
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!
根据al冰岛m的答案，我在小数点后去掉了0:
function formatBytes(bytes, decimals) {
if(bytes== 0)
{
return "0 Byte";
}
var k = 1024; //Or 1 kilo = 1000
var sizes = ["Bytes", "KB", "MB", "GB", "TB", "PB"];
var i = Math.floor(Math.log(bytes) / Math.log(k));
return parseFloat((bytes / Math.pow(k, i)).toFixed(decimals)) + " " + sizes[i];
}
