Answers:
这是一种相当简洁的方法：
static readonly string[] SizeSuffixes =
{ "bytes", "KB", "MB", "GB", "TB", "PB", "EB", "ZB", "YB" };
static string SizeSuffix(Int64 value, int decimalPlaces = 1)
{
if (decimalPlaces < 0) { throw new ArgumentOutOfRangeException("decimalPlaces"); }
if (value < 0) { return "-" + SizeSuffix(-value); }
if (value == 0) { return string.Format("{0:n" + decimalPlaces + "} bytes", 0); }
// mag is 0 for bytes, 1 for KB, 2, for MB, etc.
int mag = (int)Math.Log(value, 1024);
// 1L << (mag * 10) == 2 ^ (10 * mag)
// [i.e. the number of bytes in the unit corresponding to mag]
decimal adjustedSize = (decimal)value / (1L << (mag * 10));
// make adjustment when the value is large enough that
// it would round up to 1000 or more
if (Math.Round(adjustedSize, decimalPlaces) >= 1000)
{
mag += 1;
adjustedSize /= 1024;
}
return string.Format("{0:n" + decimalPlaces + "} {1}",
adjustedSize,
SizeSuffixes[mag]);
}这是我建议的原始实现，可能会稍慢一些，但易于遵循：
static readonly string[] SizeSuffixes =
{ "bytes", "KB", "MB", "GB", "TB", "PB", "EB", "ZB", "YB" };
static string SizeSuffix(Int64 value, int decimalPlaces = 1)
{
if (value < 0) { return "-" + SizeSuffix(-value); }
int i = 0;
decimal dValue = (decimal)value;
while (Math.Round(dValue, decimalPlaces) >= 1000)
{
dValue /= 1024;
i++;
}
return string.Format("{0:n" + decimalPlaces + "} {1}", dValue, SizeSuffixes[i]);
}
Console.WriteLine(SizeSuffix(100005000L));请记住一件事-在SI表示法中，“ kilo”通常使用小写字母k，而所有较大的单位都使用大写字母。Windows使用KB，MB，GB，因此我在上面使用KB，但是您可以考虑使用kB。
if (value == 0) { return "0"; }在函数中添加一个检查。
检出ByteSize库。这是System.TimeSpan字节！
它为您处理转换和格式化。
var maxFileSize = ByteSize.FromKiloBytes(10);
maxFileSize.Bytes;
maxFileSize.MegaBytes;
maxFileSize.GigaBytes;它还进行字符串表示和解析。
// ToString
ByteSize.FromKiloBytes(1024).ToString(); // 1 MB
ByteSize.FromGigabytes(.5).ToString(); // 512 MB
ByteSize.FromGigabytes(1024).ToString(); // 1 TB
// Parsing
ByteSize.Parse("5b");
ByteSize.Parse("1.55B");由于其他所有人都在发布他们的方法，因此我想应该发布通常用于此目的的扩展方法：
编辑：添加了int / long变体...并修复了copypasta错字...
public static class Ext
{
private const long OneKb = 1024;
private const long OneMb = OneKb * 1024;
private const long OneGb = OneMb * 1024;
private const long OneTb = OneGb * 1024;
public static string ToPrettySize(this int value, int decimalPlaces = 0)
{
return ((long)value).ToPrettySize(decimalPlaces);
}
public static string ToPrettySize(this long value, int decimalPlaces = 0)
{
var asTb = Math.Round((double)value / OneTb, decimalPlaces);
var asGb = Math.Round((double)value / OneGb, decimalPlaces);
var asMb = Math.Round((double)value / OneMb, decimalPlaces);
var asKb = Math.Round((double)value / OneKb, decimalPlaces);
string chosenValue = asTb > 1 ? string.Format("{0}Tb",asTb)
: asGb > 1 ? string.Format("{0}Gb",asGb)
: asMb > 1 ? string.Format("{0}Mb",asMb)
: asKb > 1 ? string.Format("{0}Kb",asKb)
: string.Format("{0}B", Math.Round((double)value, decimalPlaces));
return chosenValue;
}
}我会使用Extension methods，Math.Pow函数和来解决它Enums：
public static class MyExtension
{
public enum SizeUnits
{
Byte, KB, MB, GB, TB, PB, EB, ZB, YB
}
public static string ToSize(this Int64 value, SizeUnits unit)
{
return (value / (double)Math.Pow(1024, (Int64)unit)).ToString("0.00");
}
}并像这样使用它：
string h = x.ToSize(MyExtension.SizeUnits.KB);投票最多的答案的简短版本在TB值方面存在问题。
我对其进行了适当的调整，以处理tb值，并且仍然没有循环，并且还为负值添加了一些错误检查。这是我的解决方案：
static readonly string[] SizeSuffixes = { "bytes", "KB", "MB", "GB", "TB", "PB", "EB", "ZB", "YB" };
static string SizeSuffix(long value, int decimalPlaces = 0)
{
if (value < 0)
{
throw new ArgumentException("Bytes should not be negative", "value");
}
var mag = (int)Math.Max(0, Math.Log(value, 1024));
var adjustedSize = Math.Round(value / Math.Pow(1024, mag), decimalPlaces);
return String.Format("{0} {1}", adjustedSize, SizeSuffixes[mag]);
}否。主要是因为它的需求相当小众，并且可能有太多的变化。（是“ KB”，“ Kb”还是“ Ko”？是兆字节1024 * 1024字节还是1024 * 1000字节？-是的，某些地方使用了它！）
这是一个比您的选项更容易扩展的选项，但是不，库本身没有内置的选项。
private static List<string> suffixes = new List<string> { " B", " KB", " MB", " GB", " TB", " PB" };
public static string Foo(int number)
{
for (int i = 0; i < suffixes.Count; i++)
{
int temp = number / (int)Math.Pow(1024, i + 1);
if (temp == 0)
return (number / (int)Math.Pow(1024, i)) + suffixes[i];
}
return number.ToString();
} private string GetFileSize(double byteCount)
{
string size = "0 Bytes";
if (byteCount >= 1073741824.0)
size = String.Format("{0:##.##}", byteCount / 1073741824.0) + " GB";
else if (byteCount >= 1048576.0)
size = String.Format("{0:##.##}", byteCount / 1048576.0) + " MB";
else if (byteCount >= 1024.0)
size = String.Format("{0:##.##}", byteCount / 1024.0) + " KB";
else if (byteCount > 0 && byteCount < 1024.0)
size = byteCount.ToString() + " Bytes";
return size;
}
private void btnBrowse_Click(object sender, EventArgs e)
{
if (openFile1.ShowDialog() == DialogResult.OK)
{
FileInfo thisFile = new FileInfo(openFile1.FileName);
string info = "";
info += "File: " + Path.GetFileName(openFile1.FileName);
info += Environment.NewLine;
info += "File Size: " + GetFileSize((int)thisFile.Length);
label1.Text = info;
}
}这也是一种解决方法（数字1073741824.0是1024 * 1024 * 1024 aka GB）
@Servy的回答很简洁。我认为可以更简单吗？
private static string[] suffixes = new [] { " B", " KB", " MB", " GB", " TB", " PB" };
public static string ToSize(double number, int precision = 2)
{
// unit's number of bytes
const double unit = 1024;
// suffix counter
int i = 0;
// as long as we're bigger than a unit, keep going
while(number > unit)
{
number /= unit;
i++;
}
// apply precision and current suffix
return Math.Round(number, precision) + suffixes[i];
}基于NeverHopeless的优雅解决方案：
private static readonly KeyValuePair<long, string>[] Thresholds =
{
// new KeyValuePair<long, string>(0, " Bytes"), // Don't devide by Zero!
new KeyValuePair<long, string>(1, " Byte"),
new KeyValuePair<long, string>(2, " Bytes"),
new KeyValuePair<long, string>(1024, " KB"),
new KeyValuePair<long, string>(1048576, " MB"), // Note: 1024 ^ 2 = 1026 (xor operator)
new KeyValuePair<long, string>(1073741824, " GB"),
new KeyValuePair<long, string>(1099511627776, " TB"),
new KeyValuePair<long, string>(1125899906842620, " PB"),
new KeyValuePair<long, string>(1152921504606850000, " EB"),
// These don't fit into a int64
// new KeyValuePair<long, string>(1180591620717410000000, " ZB"),
// new KeyValuePair<long, string>(1208925819614630000000000, " YB")
};
/// <summary>
/// Returns x Bytes, kB, Mb, etc...
/// </summary>
public static string ToByteSize(this long value)
{
if (value == 0) return "0 Bytes"; // zero is plural
for (int t = Thresholds.Length - 1; t > 0; t--)
if (value >= Thresholds[t].Key) return ((double)value / Thresholds[t].Key).ToString("0.00") + Thresholds[t].Value;
return "-" + ToByteSize(-value); // negative bytes (common case optimised to the end of this routine)
}也许有过多的评论，但我倾向于留下它们，以防止自己在以后的访问中犯同样的错误...
没有。
但是您可以这样实现：
static double ConvertBytesToMegabytes(long bytes)
{
return (bytes / 1024f) / 1024f;
}
static double ConvertKilobytesToMegabytes(long kilobytes)
{
return kilobytes / 1024f;
}我将这里的一些答案组合成两种效果很好的方法。下面的第二种方法将从字节字符串（例如1.5.1 GB）转换回字节（例如1621350140）作为长型值。我希望这对其他寻求将字节转换为字符串然后再转换为字节的解决方案的人有用。
public static string BytesAsString(float bytes)
{
string[] suffix = { "B", "KB", "MB", "GB", "TB" };
int i;
double doubleBytes = 0;
for (i = 0; (int)(bytes / 1024) > 0; i++, bytes /= 1024)
{
doubleBytes = bytes / 1024.0;
}
return string.Format("{0:0.00} {1}", doubleBytes, suffix[i]);
}
public static long StringAsBytes(string bytesString)
{
if (string.IsNullOrEmpty(bytesString))
{
return 0;
}
const long OneKb = 1024;
const long OneMb = OneKb * 1024;
const long OneGb = OneMb * 1024;
const long OneTb = OneGb * 1024;
double returnValue;
string suffix = string.Empty;
if (bytesString.IndexOf(" ") > 0)
{
returnValue = float.Parse(bytesString.Substring(0, bytesString.IndexOf(" ")));
suffix = bytesString.Substring(bytesString.IndexOf(" ") + 1).ToUpperInvariant();
}
else
{
returnValue = float.Parse(bytesString.Substring(0, bytesString.Length - 2));
suffix = bytesString.ToUpperInvariant().Substring(bytesString.Length - 2);
}
switch (suffix)
{
case "KB":
{
returnValue *= OneKb;
break;
}
case "MB":
{
returnValue *= OneMb;
break;
}
case "GB":
{
returnValue *= OneGb;
break;
}
case "TB":
{
returnValue *= OneTb;
break;
}
default:
{
break;
}
}
return Convert.ToInt64(returnValue);
}float.Parse来double？
我知道这已经是旧线程了。但也许有人会寻找解决方案。这是我使用的和最简单的方法
public static string FormatFileSize(long bytes)
{
var unit = 1024;
if (bytes < unit)
{
return $"{bytes} B";
}
var exp = (int)(Math.Log(bytes) / Math.Log(unit));
return $"{bytes / Math.Pow(unit, exp):F2} " +
$"{("KMGTPE")[exp - 1]}B";
}我选择了JerKimballs解决方案，并对此表示赞许。但是，我想补充/指出，这确实是一个有争议的问题。在研究中（出于其他原因），我得出了以下信息。
当普通人（我听说它们存在）谈论千兆字节时，它们指的是公制，其中从原始字节数==千兆字节数等于1000乘以3的幂。但是，当然有Wikipedia中很好地总结了IEC / JEDEC标准，而不是1000的x的幂，它们有1024。对于物理存储设备（我想像亚马逊和其他逻辑设备），这意味着公制与IEC之间的差异越来越大。因此，例如1 TB == 1 TB度量标准是4的幂的1000，但是IEC正式称与1 TiB相似的数字，tebibyte则将1024的幂乘以4的幂。但是，可惜，在非技术应用中（我会以受众群体为准）规范是度量标准，目前在我自己的内部使用应用程序中，我解释了文档上的区别。但是出于显示目的，我只提供度量标准。在内部，即使它与我的应用程序无关，我也只存储字节并进行显示计算。
顺带一提，我发现.Net框架AFAIK（在4.5的化身中，我经常错了，这是我经常错的），即使在4.5版本中，它在内部任何库中均不包含任何有关内容。人们会期望某种形式的开源库在某个时候成为NuGettable，但是我承认这是一个小麻烦。另一方面，System.IO.DriveInfo和其他文件也只有字节（很长），这很清楚。
public static class MyExtension
{
public static string ToPrettySize(this float Size)
{
return ConvertToPrettySize(Size, 0);
}
public static string ToPrettySize(this int Size)
{
return ConvertToPrettySize(Size, 0);
}
private static string ConvertToPrettySize(float Size, int R)
{
float F = Size / 1024f;
if (F < 1)
{
switch (R)
{
case 0:
return string.Format("{0:0.00} byte", Size);
case 1:
return string.Format("{0:0.00} kb", Size);
case 2:
return string.Format("{0:0.00} mb", Size);
case 3:
return string.Format("{0:0.00} gb", Size);
}
}
return ConvertToPrettySize(F, ++R);
}
}如何递归：
private static string ReturnSize(double size, string sizeLabel)
{
if (size > 1024)
{
if (sizeLabel.Length == 0)
return ReturnSize(size / 1024, "KB");
else if (sizeLabel == "KB")
return ReturnSize(size / 1024, "MB");
else if (sizeLabel == "MB")
return ReturnSize(size / 1024, "GB");
else if (sizeLabel == "GB")
return ReturnSize(size / 1024, "TB");
else
return ReturnSize(size / 1024, "PB");
}
else
{
if (sizeLabel.Length > 0)
return string.Concat(size.ToString("0.00"), sizeLabel);
else
return string.Concat(size.ToString("0.00"), "Bytes");
}
}然后可以调用它：
ReturnSize(size, string.Empty);如上所述，在对数的帮助下，递归是最常用的方法。
以下函数具有3个参数：输入，输出的尺寸约束，即第三个参数。
int ByteReDim(unsigned long ival, int constraint, unsigned long *oval)
{
int base = 1 + (int) log10(ival);
(*oval) = ival;
if (base > constraint) {
(*oval) = (*oval) >> 10;
return(1 + ByteReDim((*oval), constraint, oval));
} else
return(0);
}现在让我们以几种单位转换12GB的RAM：
int main(void)
{
unsigned long RAM;
int unit; // index of below symbols array
char symbol[5] = {'B', 'K', 'M', 'G', 'T'};
unit = ByteReDim(12884901888, 12, &RAM);
printf("%lu%c\n", RAM, symbol[unit]); // output is 12884901888B
unit = ByteReDim(12884901888, 9, &RAM);
printf("%lu%c\n", RAM, symbol[unit]); // output is 12582912K
unit = ByteReDim(12884901888, 6, &RAM);
printf("%lu%c\n", RAM, symbol[unit]); // output is 12288M
unit = ByteReDim(12884901888, 3, &RAM);
printf("%lu%c\n", RAM, symbol[unit]); // output is 12G
}我将其用于Windows（二进制前缀）：
static readonly string[] BinaryPrefix = { "bytes", "KB", "MB", "GB", "TB" }; // , "PB", "EB", "ZB", "YB"
string GetMemoryString(double bytes)
{
int counter = 0;
double value = bytes;
string text = "";
do
{
text = value.ToString("0.0") + " " + BinaryPrefix[counter];
value /= 1024;
counter++;
}
while (Math.Floor(value) > 0 && counter < BinaryPrefix.Length);
return text;
}我已经将此（几乎没有修改）合并到我的项目的UWP DataBinding Converter中，并认为它可能对其他人也有用。
代码是：
using System;
using System.Text;
using Windows.UI.Xaml.Data;
namespace MyApp.Converters
{
public class ByteSizeConverter : IValueConverter
{
static readonly string[] sSizeSuffixes = { "bytes", "KB", "MB", "GB", "TB", "PB", "EB", "ZB", "YB" };
// The number of decimal places the formatter should include in the scaled output - default 1dp
public int DecimalPlaces { get; set; } = 1;
public object Convert(object value, Type targetType, object parameter, string language)
{
Int64 intVal = System.Convert.ToInt64(value);
return SizeSuffix(intVal);
}
public object ConvertBack(object value, Type targetType, object parameter, string language)
{
// TODO: Parse string into number and suffix
// Scale number by suffix multiplier to get bytes
throw new NotImplementedException();
}
string SizeSuffix(Int64 value)
{
if (this.DecimalPlaces < 0) { throw new ArgumentOutOfRangeException(String.Format("DecimalPlaces = {0}", this.DecimalPlaces)); }
if (value < 0) { return "-" + SizeSuffix(-value); }
if (value == 0) { return string.Format("{0:n" + this.DecimalPlaces + "} bytes", 0); }
// magnitude is 0 for bytes, 1 for KB, 2, for MB, etc.
int magnitude = (int)Math.Log(value, 1024);
// clip magnitude - only 8 values currently supported, this prevents out-of-bounds exception
magnitude = Math.Min(magnitude, 8);
// 1L << (magnitude * 10) == 2 ^ (10 * magnitude) [i.e. the number of bytes in the unit corresponding to magnitude]
decimal adjustedSize = (decimal)value / (1L << (magnitude * 10));
// make adjustment when the value is large enough that it would round up to 1000 or more
if (Math.Round(adjustedSize, this.DecimalPlaces) >= 1000)
{
magnitude += 1;
adjustedSize /= 1024;
}
return String.Format("{0:n" + this.DecimalPlaces + "} {1}", adjustedSize, sSizeSuffixes[magnitude]);
}
}
}若要使用它，请将本地资源添加到您的UserControl或Page XAML：
<UserControl.Resources>
<converters:ByteSizeConverter x:Key="ByteFormat" DecimalPlaces="3" />
</UserControl.Resources>在数据绑定模板或数据绑定实例中引用它：
<TextBlock HorizontalAlignment="Left" VerticalAlignment="Center"
Text="{x:Bind MyItem.FileSize_bytes, Mode=OneWay, Converter={StaticResource ByteFormat}}" />嘿，presto。魔术发生了。
https://github.com/logary/logary/blob/master/src/Logary/DataModel.fs#L832-L837
let scaleBytes (value : float) : float * string =
let log2 x = log x / log 2.
let prefixes = [| ""; "Ki"; "Mi"; "Gi"; "Ti"; "Pi" |] // note the capital K and the 'i'
let index = int (log2 value) / 10
1. / 2.**(float index * 10.),
sprintf "%s%s" prefixes.[index] (Units.symbol Bytes)（免责声明：我写了这段代码，甚至是链接中的代码！）