CodeItBetter Programming Another VB Programming Blog

'System & API - Common Dialog option through API
Option Compare Database
Option Explicit
 
Public Const MaxDWord As Double = 4294967295#
Public Const mMax_Path = 4096
 
Public Type typOpenFilename
    lStructSize As Long
    hwndOwner As Long
    hInstance As Long
    lpstrFilter As String
    lpstrCustomFilter As String
    nMaxCustFilter As Long
    nFilterIndex As Long
    lpstrFile As String
    nMaxFile As Long
    lpstrFileTitle As String
    nMaxFileTitle As Long
    lpstrInitialDir As String
    lpstrTitle As String
    Flags As Long
    nFileOffset As Integer
    nFileExtension As Integer
    lpstrDefExt As String
    lCustData As Long
    lpfnHook As Long
    lpTemplateName As String
End Type
 
Public Type typChooseColor
    lStructSize As Long
    hwndOwner As Long
    hInstance As Long
    rgbResult As Long
    lpCustColors As String
    Flags As Long
    lCustData As Long
    lpfnHook As Long
    lpTemplateName As String
End Type
 
Public Declare Function apiGetTickCount Lib "kernel32" Alias "GetTickCount" () As Long
Public Declare Function apiGetOpenFilename Lib "comdlg32.dll" Alias "GetOpenFileNameA" (ptypOpenFilename As typOpenFilename) As Long
Public Declare Function apiGetSaveFileName Lib "comdlg32.dll" Alias "GetSaveFileNameA" _
    (ptypOpenFilename As typOpenFilename) As Long
Public Declare Function apiGetChooseColor Lib "comdlg32.dll" Alias "ChooseColorA" _
    (ptypChooseColor As typChooseColor) As Long
 
'---- my design based on MS Help - Selects a colour using the common dialog box
Public Function ColourSelection(Optional lngFlags, Optional lngInitColour) As Long
    '---- Uses the common dialog box / colour selection
    '---- usual flags are : 1 - starting colour specified, 2 - full open
    '----   so use 3 as the flag every time
    '---- Returns :
    '----   -1 : Failed/cancelled
    '----   >=0 : colour in long
    Dim cChoose As typChooseColor
    Dim lngRes As Long
    Dim intI As Integer
    Dim bytCols As Byte
 
    On Error Resume Next
 
    ColourSelection = -1
 
    With cChoose
        '---- default info
        .lStructSize = Len(cChoose)
        .hwndOwner = 0
        .hInstance = 0
        .lpCustColors = StrConv(bytCols, vbUnicode)
        '---- optional bits
        .Flags = 0
        .rgbResult = 0
        If Not IsMissing(lngFlags) Then .Flags = lngFlags
        If Not IsMissing(lngInitColour) Then .rgbResult = lngInitColour
        lngRes = apiGetChooseColor(cChoose)
        If lngRes > 0 Then ColourSelection = .rgbResult
    End With
    If Not Err.Number = 0 Then ColourSelection = -1
End Function
 
'---- Selects a/several file(s) using common dialogs
Public Function FileSelection(ByVal strInitDir As String, ByVal lngFlag As Long, ByVal strFilter As String, _
    ByVal lngFilterIndex As Long, ByVal blnOpen As Boolean, Optional strTitle, Optional strFileExtension, _
    Optional lngOwnerHwnd) As String
    '---- Selects one or more filenames
    '---- Requires
    '----   inital directory to open in
    '----   flags for opening

    '---- usual flags are :
    '----   &H200000 - use long filenames
    '----   &H80000 - Explorer type window
    '----   &H200 - multi select
    '----   &H4 - hide read only option on box - v useful
    '----   &H8 - force same dir as when opened
    '----   &H1000 - file must exist - useful for opening
    '---- usual I use : &H280004

    '---- Returns a string holding either :
    '----   nothing
    '----   path and filename
    '----   path chr$(0) filenames separated by chr$(0)
    '---- NOTE : current max chars = 257 ... I think expand if neccessary

    Dim strTemp As String
    Dim lngReturn As Long, lngP As Long, lngO As Long
    Dim cOpenFilename As typOpenFilename
 
    On Error Resume Next
 
    With cOpenFilename
 
        '---- Default values according to another developer
        .lStructSize = Len(cOpenFilename)
        .hInstance = 0
        .nFilterIndex = 1
        .nFileOffset = 0
        .lpstrFile = String(5000, 0)
        .nMaxFile = Len(.lpstrFile) - 1
        .lpstrFileTitle = .lpstrFile
        .nMaxFileTitle = .nMaxFile
 
        If Not IsMissing(strFileExtension) Then .lpstrDefExt = strFileExtension
        '---- Bits like the common dialog control
        If blnOpen Then
            .lpstrTitle = "Open a file..."
        Else
            .lpstrTitle = "Save file as..."
        End If
        If Not IsMissing(strTitle) Then .lpstrTitle = strTitle
 
        '---- messing
        '----   default filter

        '---- each filter is separated by a character of 0 - Name - filter - name filter (etc..)
        '---- example :
        '        .lpstrFilter = "All Files" & Chr$(0) & "*.*" & Chr$(0) & "Text Files" & Chr$(0) & "*.txt;*.csv"
        '---- replace filter with the selection chosen by the programmer...
        .lpstrFilter = "All Files (*.*)" & Chr$(0) & "*.*"
 
        lngO = 1
        lngP = InStr(1, strFilter, "|")
        If lngP > 0 Then
            strTemp = ""
            Do Until lngP = 0
                strTemp = strTemp & IIf(Len(strTemp) > 0, Chr$(0), "") & Mid$(strFilter, lngO, lngP - lngO)
                lngO = lngP + 1
                lngP = InStr(lngP + 1, strFilter, "|")
            Loop
            strTemp = strTemp & Chr$(0) & Right$(strFilter, Len(strFilter) - lngO + 1)
        Else
            strTemp = strFilter
        End If
        .lpstrFilter = strTemp
 
        .Flags = lngFlag
 
        .hwndOwner = 0
        If Not IsMissing(lngOwnerHwnd) Then .hwndOwner = lngOwnerHwnd
        '---- remark out the next line - or amend it as applicable
        If .hwndOwner = 0 Then .hwndOwner = Application.hWndAccessApp
 
        .lpstrInitialDir = strInitDir
 
    End With
 
    '---- is the dialog box an open or save?
    If blnOpen Then
        lngReturn = apiGetOpenFilename(cOpenFilename)
    Else
        lngReturn = apiGetSaveFileName(cOpenFilename)
    End If
 
    '---- send back the selected file(s)
    If lngReturn = 0 Then
        FileSelection = ""
    Else
        FileSelection = RemoveNonPChars(cOpenFilename.lpstrFile)
    End If
End Function
 
Public Function RemoveNonPChars(ByVal strText As String) As String
    '---- gets rid of the extra chr$(0)'s in the text
    '---- by looking for two chr$(0)'s together (only happens at the end...)
    '---- NOTE : only removes those at the end of the string - for multi means that you can get the filenames...
    Dim lngP As Long
    On Error Resume Next
    RemoveNonPChars = " "
    If Len(strText) = 0 Then Exit Function
    lngP = InStr(1, strText, Chr$(0) & Chr$(0))
    If lngP > 1 Then RemoveNonPChars = Left$(strText, lngP - 1)
    If Not Err.Number = 0 Then
        RemoveNonPChars = " "
        Err.Clear
    End If
End Function