'=======================================================
'「ファイルを開く」ダイアログ表示
'-------------------------------------------------------
't_mizu@mail.goo.ne.jpさんからの投稿 1999/03/01
'=======================================================
Option Compare Database
Option Explicit

Const OFN_READONLY = &H1
Const OFN_OVERWRITEPROMPT = &H2
Const OFN_HIDEREADONLY = &H4
Const OFN_NOCHANGEDIR = &H8
Const OFN_SHOWHELP = &H10
Const OFN_ENABLEHOOK = &H20
Const OFN_ENABLETEMPLATE = &H40
Const OFN_ENABLETEMPLATEHANDLE = &H80
Const OFN_NOVALIDATE = &H100
Const OFN_ALLOWMULTISELECT = &H200
Const OFN_EXTENSIONDIFFERENT = &H400
Const OFN_PATHMUSTEXIST = &H800
Const OFN_FILEMUSTEXIST = &H1000
Const OFN_CREATEPROMPT = &H2000
Const OFN_SHAREAWARE = &H4000
Const OFN_NOREADONLYRETURN = &H8000
Const OFN_NOTESTFILECREATE = &H10000
Const OFN_NONETWORKBUTTON = &H20000
Const OFN_NOLONGNAMES = &H40000 ' force no long names for 4.x modules
Const OFN_EXPLORER = &H80000 ' new look commdlg
Const OFN_NODEREFERENCELINKS = &H100000
Const OFN_LONGNAMES = &H200000 ' force long names for 3.x modules

Declare Function GetOpenFileName Lib "COMDLG32.DLL" Alias "GetOpenFileNameA" (pOpenfilename As OpenFileName) As Long

'「ファイルを開く」ダイアログ表示用構造体
Type OpenFileName
        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

'「ファイルを開く」ダイアログを開いてファイル選択
' 引数
' hWnd : 表示元ウィンドウハンドル（指定なしの場合、0 を渡す）
' Title : ダイアログボックスのウィンドウタイトル
' InitDir : 初期ディレクトリ
' リターン値
' = "" : ファイル選択キャンセル
' <> "" :選択されたファイル名（フルパス）
Public Function Select_OpenFileName(ByVal hWnd As Long, Optional Title As Variant, Optional InitDir As Variant) As String
        Dim OF As OpenFileName
        Dim tmp As String
        Dim stu As Long
        Dim filter As String

        tmp = String$(5120, Chr$(0))
        filter = "全て(*.*)" + Chr$(0) + "*.*" + Chr$(0) + Chr$(0)
        With OF
                .lStructSize = Len(OF) '構造体長
                .hwndOwner = hWnd 'Ownerハンドル
                .lpstrFile = tmp '戻り値バッファ
                .nMaxFile = 5120 '戻り値バッファ長
                .lpstrFilter = filter
                .nFilterIndex = 1
                .Flags = OFN_FILEMUSTEXIST Or OFN_HIDEREADONLY Or OFN_PATHMUSTEXIST
                If Not IsMissing(Title) Then .lpstrTitle = Title 'ダイアログタイトル
                If Not IsMissing(InitDir) Then .lpstrInitialDir = InitDir '初期ディレクトリ
        End With
        stu = GetOpenFileName(OF)
        If stu Then
                Select_OpenFileName = Left$(OF.lpstrFile, InStr(OF.lpstrFile, Chr$(0)) - 1)
        End If
End Function