我如何获得一个人类可读的文件大小字节缩写使用。net ?
例子: 输入7,326,629,显示6.98 MB
我如何获得一个人类可读的文件大小字节缩写使用。net ?
例子: 输入7,326,629,显示6.98 MB
当前回答
我猜你要找的是“1.4 MB”而不是“1468006字节”?
我不认为在。net中有内置的方法来做到这一点。你只需要找出哪个单元是合适的,然后格式化它。
编辑:这里有一些示例代码来做到这一点:
http://www.codeproject.com/KB/cpp/formatsize.aspx
其他回答
我的观点是:
千字节的前缀是kB(小写K) 由于这些函数用于表示目的,因此应该提供区域性,例如:CurrentCulture,“{0时。##}{1}",文件大小,单位); 根据上下文,千字节可以是1000字节或1024字节。MB、GB等也是如此。
我喜欢使用以下方法(它支持高达tb,这在大多数情况下已经足够了,但它可以很容易地扩展):
private string GetSizeString(long length)
{
long B = 0, KB = 1024, MB = KB * 1024, GB = MB * 1024, TB = GB * 1024;
double size = length;
string suffix = nameof(B);
if (length >= TB) {
size = Math.Round((double)length / TB, 2);
suffix = nameof(TB);
}
else if (length >= GB) {
size = Math.Round((double)length / GB, 2);
suffix = nameof(GB);
}
else if (length >= MB) {
size = Math.Round((double)length / MB, 2);
suffix = nameof(MB);
}
else if (length >= KB) {
size = Math.Round((double)length / KB, 2);
suffix = nameof(KB);
}
return $"{size} {suffix}";
}
请记住,这是为c# 6.0(2015)编写的,因此对于较早的版本可能需要进行一些编辑。
这个问题很老了,但是一个非常快速的c#函数可以是:
public static string PrettyPrintBytes(long numBytes)
{
if (numBytes < 1024)
return $"{numBytes} B";
if (numBytes < 1048576)
return $"{numBytes / 1024d:0.##} KB";
if (numBytes < 1073741824)
return $"{numBytes / 1048576d:0.##} MB";
if (numBytes < 1099511627776)
return $"{numBytes / 1073741824d:0.##} GB";
if (numBytes < 1125899906842624)
return $"{numBytes / 1099511627776d:0.##} TB";
if (numBytes < 1152921504606846976)
return $"{numBytes / 1125899906842624d:0.##} PB";
return $"{numBytes / 1152921504606846976d:0.##} EB";
}
每次调用只有一次强制转换和一次除法,最多只能进行6次比较。在进行基准测试时,我发现字符串插值比使用string . format()快得多。
这可能不是最有效或最优化的方法,但如果您不熟悉对数数学,它更容易阅读,并且对于大多数情况来说应该足够快。
string[] sizes = { "B", "KB", "MB", "GB", "TB" };
double len = new FileInfo(filename).Length;
int order = 0;
while (len >= 1024 && order < sizes.Length - 1) {
order++;
len = len/1024;
}
// Adjust the format string to your preferences. For example "{0:0.#}{1}" would
// show a single decimal place, and no space.
string result = String.Format("{0:0.##} {1}", len, sizes[order]);
这里没有什么东西完全符合我的需要,我根据这个线程制作了我自己的,所以这里是我的长扩展,允许您根据标准选择格式要求。
绝对不是最快的,但很灵活。支持EB/EiB。
// <summary>
/// <paramref name="byteCount"/> The original size in bytes ( 8 bits )
/// <paramref name="notationFormat"/> is supported in the following ways:
/// [ 'B' / 'b' : Binary : Kilobyte (KB) is 1024 bytes, Megabyte (MB) is 1048576 bytes, etc ]
/// [ 'I' / 'i' : IEC: Kibibyte (KiB) is 1024 bytes, Mebibyte (MiB) is 1048576 bytes, etc ]
/// [ 'D' / 'd' : Decimal : Kilobyte (KB) is 1000 bytes, Megabyte (MB) is 1000000 bytes, etc ]
/// </summary>
public static string ToDataSizeString( this long byteCount, char notationFormat = 'b' )
{
char[] supportedFormatChars = { 'b', 'i', 'd' };
var lowerCaseNotationFormat = char.ToLowerInvariant( notationFormat );
// Stop shooting holes in my ship!
if ( !supportedFormatChars.Contains( lowerCaseNotationFormat ) )
{
throw new ArgumentException( $"notationFormat argument '{notationFormat}' not supported" );
}
long ebLimit = 1152921504606846976;
long pbLimit = 1125899906842624;
long tbLimit = 1099511627776;
long gbLimit = 1073741824;
long mbLimit = 1048576;
long kbLimit = 1024;
var ebSuffix = "EB";
var pbSuffix = "PB";
var tbSuffix = "TB";
var gbSuffix = "GB";
var mbSuffix = "MB";
var kbSuffix = "KB";
var bSuffix = " B";
switch ( lowerCaseNotationFormat )
{
case 'b':
// Sweet as
break;
case 'i':
// Limits stay the same, suffixes need changed
ebSuffix = "EiB";
pbSuffix = "PiB";
tbSuffix = "TiB";
gbSuffix = "GiB";
mbSuffix = "MiB";
kbSuffix = "KiB";
bSuffix = " B";
break;
case 'd':
// Suffixes stay the same, limits need changed
ebLimit = 1000000000000000000;
pbLimit = 1000000000000000;
tbLimit = 1000000000000;
gbLimit = 1000000000;
mbLimit = 1000000;
kbLimit = 1000;
break;
default:
// Should have already Excepted, but hey whatever
throw new ArgumentException( $"notationFormat argument '{notationFormat}' not supported" );
}
string fileSizeText;
// Exa/Exbi sized
if ( byteCount >= ebLimit )
{
fileSizeText = $"{( (double)byteCount / ebLimit ):N1} {ebSuffix}";
}
// Peta/Pebi sized
else if ( byteCount >= pbLimit )
{
fileSizeText = $"{( (double)byteCount / pbLimit ):N1} {pbSuffix}";
}
// Tera/Tebi sized
else if ( byteCount >= tbLimit )
{
fileSizeText = $"{( (double)byteCount / tbLimit ):N1} {tbSuffix}";
}
// Giga/Gibi sized
else if ( byteCount >= gbLimit )
{
fileSizeText = $"{( (double)byteCount / gbLimit ):N1} {gbSuffix}";
}
// Mega/Mibi sized
else if ( byteCount >= mbLimit )
{
fileSizeText = $"{( (double)byteCount / mbLimit ):N1} {mbSuffix}";
}
// Kilo/Kibi sized
else if ( byteCount >= kbLimit )
{
fileSizeText = $"{( (double)byteCount / kbLimit ):N1} {kbSuffix}";
}
// Byte sized
else
{
fileSizeText = $"{byteCount} {bSuffix}";
}
return fileSizeText;
}