VB Code:
  1. Declare Function GetUserName Lib "advapi32.dll" Alias "GetUserNameA" (ByVal lpBuffer As String, nSize As Long) As Long

  2.  
  3. Function UserName() as String

  4.  
  5.     Dim strBuffer As String * 25

  6.     

  7.     Dim ret As Long

  8.  
  9.     ret = GetUserName(strBuffer , 25)

  10.     

  11.     UserName = Left(strBuffer, InStr(strBuffer, Chr(0)) - 1)

  12.  
  13. End Function