Read a binary file into an array

Question

What's the fastest way (using VB6) to read an entire, large, binary file into an array?

Answer 1

Here's one way, although you are limited to files around 2 GB in size.

  Dim fileNum As Integer
  Dim bytes() As Byte

  fileNum = FreeFile
  Open "C:\test.bin" For Binary As fileNum
  ReDim bytes(LOF(fileNum) - 1)
  Get fileNum, , bytes
  Close fileNum

Answer 2

You can compare these two

Private Function ReadFile1(sFile As String) As Byte()
    Dim nFile       As Integer

    nFile = FreeFile
    Open sFile For Input Access Read As #nFile
    If LOF(nFile) > 0 Then
        ReadFile1 = InputB(LOF(nFile), nFile)
    End If
    Close #nFile
End Function

Private Function ReadFile2(sFile As String) As Byte()
    Dim nFile       As Integer

    nFile = FreeFile
    Open sFile For Binary Access Read As #nFile
    If LOF(nFile) > 0 Then
        ReDim ReadFile2(0 To LOF(nFile) - 1)
        Get nFile, , ReadFile2
    End If
    Close #nFile
End Function

I prefer the second one but it has this nasty side effect. If sFile does not exists For Binary mode creates an empty file no matter that Access Read is used.