C#/VB取文件的大小 （KB,MB,GB...）

 VB:

[code]Public Function GetFileSize(ByVal iFileSizeKB As Long) As String
Dim iFileSizeMB As Integer
Dim iFileSizeGB As Integer

If (iFileSizeKB >= 1024) Then
iFileSizeMB = iFileSizeKB / 1024
If (iFileSizeMB >= 1024) Then
iFileSizeGB = iFileSizeMB / 1024
End If
End If

If (iFileSizeGB > 0) Then
Return iFileSizeGB.ToString() + " GB"
ElseIf (iFileSizeMB > 0) Then
Return iFileSizeMB.ToString() + " MB"
Else
Return iFileSizeKB.ToString() + " KB"
End If
End Function

调用方式：
  dim sFileFullName as String ="your file full name"
  dim iFileSize as Integer = New System.IO.FileInfo(sFileFullName ).Length / 1024
  dim sFileSize as String  

  sFileSize = GetFileSize(iFileSize)  
===========================================================================================

C#

[code]public string GetFileSize(string sFileFullName)
{
FileInfo fiInput = new FileInfo(sFileFullName);
double len = fiInput.Length;

string[] sizes = { "B", "KB", "MB", "GB" };
int order = 0;
while (len >= 1024 && order + 1 < sizes.Length)
{
order++;
len = len / 1024;
}

string filesize = String.Format("{0:0.##} {1}", len, sizes[order]);
return filesize;
}

[code] public static bool FileIsLargerThan1KB(string sFileFullName)
{
FileInfo fiInput = new FileInfo(sFileFullName);
double len = fiInput.Length;

len = len / 1024 / 1024;
return len > 1;

}

调用方式：

 string sFileFullName ="your file full name";

 string sFileSize = GetFileSize(sFileFullName );

其它：

            string sTEST = @"C:\part1\2014\201405\aa.txt";
            string s1 = System.IO.Path.GetFileName(sTEST); // get short file name
            string s2 = System.IO.Directory.GetParent(sTEST).FullName; // get folder
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原文：https://blog.csdn.net/keenweiwei/article/details/30083197