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
检查我的ByteSize库。这是系统的问题。TimeSpan for bytes!
它为您处理转换和格式化。
var maxFileSize = ByteSize.FromKiloBytes(10);
maxFileSize.Bytes;
maxFileSize.MegaBytes;
maxFileSize.GigaBytes;
它还可以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");
其他回答
比如@NET3的解决方案。使用shift而不是除法来测试字节的范围,因为除法占用更多的CPU成本。
private static readonly string[] UNITS = new string[] { "B", "KB", "MB", "GB", "TB", "PB", "EB" };
public static string FormatSize(ulong bytes)
{
int c = 0;
for (c = 0; c < UNITS.Length; c++)
{
ulong m = (ulong)1 << ((c + 1) * 10);
if (bytes < m)
break;
}
double n = bytes / (double)((ulong)1 << (c * 10));
return string.Format("{0:0.##} {1}", n, UNITS[c]);
}
这是我编的,效果很好。
public string[] DetermineDigitalSize(string filename)
{
string[] result = new string[2];
string[] sizes = { "B", "KB", "MB", "GB", "GB" };
double len = new FileInfo(filename).Length;
double adjustedSize = len;
double testSize = 0;
int order = 0;
while (order< sizes.Length-1)
{
testSize = adjustedSize / 1024;
if (testSize >= 1) { adjustedSize = testSize; order++; }
else { break; }
}
result[0] = $"{adjustedSize:f2}";
result[1] = sizes[order];
return result;
}
[DllImport ( "Shlwapi.dll", CharSet = CharSet.Auto )]
public static extern long StrFormatByteSize (
long fileSize
, [MarshalAs ( UnmanagedType.LPTStr )] StringBuilder buffer
, int bufferSize );
/// <summary>
/// Converts a numeric value into a string that represents the number expressed as a size value in bytes, kilobytes, megabytes, or gigabytes, depending on the size.
/// </summary>
/// <param name="filelength">The numeric value to be converted.</param>
/// <returns>the converted string</returns>
public static string StrFormatByteSize (long filesize) {
StringBuilder sb = new StringBuilder( 11 );
StrFormatByteSize( filesize, sb, sb.Capacity );
return sb.ToString();
}
来自:http://www.pinvoke.net/default.aspx/shlwapi/StrFormatByteSize.html
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。
下面是一个Log10的方法:
using System;
class Program {
static string NumberFormat(double n) {
var n2 = (int)Math.Log10(n) / 3;
var n3 = n / Math.Pow(1e3, n2);
return String.Format("{0:f3}", n3) + new[]{"", " k", " M", " G"}[n2];
}
static void Main() {
var s = NumberFormat(9012345678);
Console.WriteLine(s == "9.012 G");
}
}
https://learn.microsoft.com/dotnet/api/system.math.log10