by Detonate (4 Submissions)
Category: Files/File Controls/Input/Output
Compatability: Visual Basic 3.0
Difficulty: Beginner
Date Added: Wed 3rd February 2021
Rating: 
(5 Votes)
Determines the filetype (PE Executable, GIF Image, Word Document, etc) using the file header/contents, as opposed to using the file extension. Supported types: PE Executable, INI File, AVI Movie, WAV Audio, Word document, Access database, GIF Image, MP3 audio, BMP image, TIFF image, ZIP archive, ARJ archive, RAR archive, HTML/HTA docs, JPEG image, Visual Basic files. If it can't determine the filetype, itll try and determine if the file is text or binary.
Inputs
Public Function GetFileType(xFile As String)
'xFile is the full path:\filename of the file to test.
Code Returns
Returns a string indicating the filetype, or if the file is an unknown text or unknown binary file.
VBcodersPublic Function GetFileType(xFile As String) As String
On Error Resume Next
Dim ID As String * 300
If Dir$(xFile) = "" Then
GetFileType = "NOT FOUND"
Exit Function
End If
Open xFile For Binary Access Read As #1
Get #1, 1, ID
Close #1
If Left(ID, 2) = "MZ" Or Left(ID, 2) = "ZM" Then
GetFileType = "PE Executable"
Exit Function
ElseIf Left(ID, 1) = "[" And InStr(1, Left(ID, 100), "]") > 0 Then
GetFileType = "INI File"
Exit Function
ElseIf Mid(ID, 9, 8) = "AVI LIST" Then
GetFileType = "AVI Movie File"
Exit Function
ElseIf Left(ID, 4) = "RIFF" Then
GetFileType = "WAV Audio File"
Exit Function
ElseIf Left(ID, 4) = Chr(208) & Chr(207) & Chr(17) & Chr(224) Then
GetFileType = "Microsoft Word Document"
Exit Function
ElseIf Mid(ID, 5, 15) = "Standard Jet DB" Then
GetFileType = "Microsoft Access Database"
Exit Function
ElseIf Left(ID, 3) = "GIF" Or InStr(1, ID, "GIF89") > 0 Then
GetFileType = "GIF Image File"
Exit Function
ElseIf Left(ID, 1) = Chr(255) And Mid(ID, 5, 1) = Chr(0) Then
GetFileType = "MP3 Audio File"
Exit Function
ElseIf Left(ID, 2) = "BM" Then
GetFileType = "BMP (Bitmap) Image File"
Exit Function
ElseIf Left(ID, 3) = "II*" Then
GetFileType = "TIFF Image File"
Exit Function
ElseIf Left(ID, 2) = "PK" Then
GetFileType = "ZIP Archive File"
Exit Function
ElseIf InStr(1, LCase(ID), "") > 0 Or InStr(1, LCase(ID), " 0 Then
GetFileType = "HTML Document File"
Exit Function
ElseIf UCase(Left(ID, 3)) = "RAR" Then
GetFileType = "RAR Archive File"
Exit Function
ElseIf Left(ID, 2) = Chr(96) & Chr(234) Then
GetFileType = "ARJ Archive File"
Exit Function
ElseIf Left(ID, 3) = Chr(255) & Chr(216) & Chr(255) Then
GetFileType = "JPEG Image File"
Exit Function
ElseIf InStr(1, ID, "Type=") > 0 And InStr(1, ID, "Reference=") > 0 Then
GetFileType = "Visual Basic Project File"
Exit Function
ElseIf Left(ID, 8) = "VBGROUP " Then
GetFileType = "Visual Basic Group Project File"
Exit Function
ElseIf Left(ID, 8) = "VERSION " & InStr(1, ID, vbCrLf & "Begin") > 0 Then
GetFileType = "Visual Basic Form File"
Exit Function
Else
'Unknown file... make a weak attempt to determine if the file is text or binary
If InStr(1, ID, Chr$(255)) > 0 Or InStr(1, ID, Chr$(1)) > 0 Or InStr(1, ID, Chr$(2)) > 0 Or InStr(1, ID, Chr$(3)) > 0 Then
GetFileType = "Unknown binary file"
Else
GetFileType = "Unknown text file"
End If
Exit Function
End If
End Function
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