C#/VB取文件的大小 （KB,MB,GB...）

 VB:

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#

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;
        }

 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.youkuaiyun.com/keenweiwei/article/details/30083197