使用 GetOpenFileName 代替 OpenFileDialog

Question

我无法在我的应用程序中使用 OpenFileDialog。

作为替代方案，我使用 GetOpenFileName() 方法：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Runtime.InteropServices;

namespace Reader
{
    [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Auto)]
    public class OpenFileName
    {
        public int lstructSize;
        public IntPtr hwndOwner;
        public IntPtr hInstance;
        public string lpstrFilter = null;
        public string lpstrCustomFilter = null;
        public int lMaxCustomFilter;
        public int lFilterIndex;
        public string lpstrFile = null;
        public int lMaxFile = 0;
        public string lpstrFileTitle = null;
        public int lMaxFileTitle = 0;
        public string lpstrInitialDir = null;
        public string lpstrTitle = null;
        public int lFlags;
        public ushort nFileOffset;
        public ushort nFileExtension;
        public string lpstrDefExt = null;
        public int lCustData;
        public int lpfHook;
        public int lpTemplateName;
    }

    public class OpenDialog
    {
        [DllImport("Comdlg32.dll",CharSet = CharSet.Auto)]
        public static extern bool GetOpenFileName([In, Out] OpenFileName ofn);
    }
}

然后在按钮的 OnClick 事件中使用它，如下所示：

OpenFileName qofn = new OpenFileName();

qofn.lstructSize = Marshal.SizeOf(qofn);
qofn.lpstrFile = "";
qofn.lMaxFile = 256;
qofn.lpstrFileTitle = "";
qofn.lMaxFileTitle = 64;
qofn.hInstance = this.Handle;
source.Text = "Wait...";
if (OpenDialog.GetOpenFileName(qofn))
{
    MessageBox.Show("ofn.file: " + qofn. lpstrFile );
}

当应用程序运行并单击按钮并且我尝试打开文件时，会发生以下情况：

第一次尝试：

它返回我的文件的路径，但不是 c:\dira\dirb\dirc\filename.ext 我有 c:\dira\dirb\dircfilename.ext 文件名前没有“\”

第二次尝试

一切正常

下一步： 存在随机崩溃，例如随机访问冲突，或 GUI 冻结，并且即使在任务管理器中也无法终止应用程序进程，或其他错误。

通常，对话框会工作 2-3 次，然后应用程序就会永久崩溃。

我的代码有什么问题吗？

编辑：

我无法使用OpenFileDialog。我正在使用 WinPE 4.0（Windows 评估和部署工具包 ADK）。当我尝试 OpenFileDIalog 时，它会抛出运行时错误 80040111。可能是因为核心不支持（就像Server Core不支持OpenFileDialog，错误是一样的）。可能在 WinPE 4.0 上，他们在记事本等应用程序中使用 GetOpenFileName。这对他们有用。

Answer 1

好的，我找到了这个微软示例并且它有效：

// Copyright
// Microsoft Corporation
// All rights reserved

// OpenFileDlg.cs

using System;
using System.Text;
using System.Runtime.InteropServices;

/*
typedef struct tagOFN { 
  DWORD         lStructSize; 
  HWND          hwndOwner; 
  HINSTANCE     hInstance; 
  LPCTSTR       lpstrFilter; 
  LPTSTR        lpstrCustomFilter; 
  DWORD         nMaxCustFilter; 
  DWORD         nFilterIndex; 
  LPTSTR        lpstrFile; 
  DWORD         nMaxFile; 
  LPTSTR        lpstrFileTitle; 
  DWORD         nMaxFileTitle; 
  LPCTSTR       lpstrInitialDir; 
  LPCTSTR       lpstrTitle; 
  DWORD         Flags; 
  WORD          nFileOffset; 
  WORD          nFileExtension; 
  LPCTSTR       lpstrDefExt; 
  LPARAM        lCustData; 
  LPOFNHOOKPROC lpfnHook; 
  LPCTSTR       lpTemplateName; 
#if (_WIN32_WINNT >= 0x0500)
  void *        pvReserved;
  DWORD         dwReserved;
  DWORD         FlagsEx;
#endif // (_WIN32_WINNT >= 0x0500)
} OPENFILENAME, *LPOPENFILENAME; 
*/

[ StructLayout( LayoutKind.Sequential, CharSet=CharSet.Auto )]  
public class OpenFileName 
{
    public int      structSize = 0;
    public IntPtr   dlgOwner = IntPtr.Zero; 
    public IntPtr   instance = IntPtr.Zero;

    public String   filter = null;
    public String   customFilter = null;
    public int      maxCustFilter = 0;
    public int      filterIndex = 0;

    public String   file = null;
    public int      maxFile = 0;

    public String   fileTitle = null;
    public int      maxFileTitle = 0;

    public String   initialDir = null;

    public String   title = null;   

    public int      flags = 0; 
    public short    fileOffset = 0;
    public short    fileExtension = 0;

    public String   defExt = null; 

    public IntPtr   custData = IntPtr.Zero;  
    public IntPtr   hook = IntPtr.Zero;  

    public String   templateName = null; 

    public IntPtr   reservedPtr = IntPtr.Zero; 
    public int      reservedInt = 0;
    public int      flagsEx = 0;
}

public class LibWrap
{
    //BOOL GetOpenFileName(LPOPENFILENAME lpofn);

    [ DllImport( "Comdlg32.dll", CharSet=CharSet.Auto )]                
    public static extern bool GetOpenFileName([ In, Out ] OpenFileName ofn );   
}

public class App
{
    public static void Main()
    {
        OpenFileName ofn = new OpenFileName();

        ofn.structSize = Marshal.SizeOf( ofn );

        ofn.filter = "Log files\0*.log\0Batch files\0*.bat\0";

        ofn.file = new String( new char[ 256 ]);
        ofn.maxFile = ofn.file.Length;

        ofn.fileTitle = new String( new char[ 64 ]);
        ofn.maxFileTitle = ofn.fileTitle.Length;    

        ofn.initialDir = "C:\\";
        ofn.title = "Open file called using platform invoke...";
        ofn.defExt = "txt";

        if( LibWrap.GetOpenFileName( ofn ))
        {
            Console.WriteLine( "Selected file with full path: {0}", ofn.file );
            Console.WriteLine( "Selected file name: {0}", ofn.fileTitle );
            Console.WriteLine( "Offset from file name: {0}", ofn.fileOffset );
            Console.WriteLine( "Offset from file extension: {0}", ofn.fileExtension );
        }
    }
}

Answer 2

OpenFileDlg 示例（如 Arie 的答案中使用的示例）可在 这里。

该页面有 C#、C++ 和 VB 示例。我已经在 WinPE 5.1 中测试了 VB 示例，除了文件类型过滤器之外，它运行良好；它始终显示所有文件类型。

我惊讶地发现，即使在我的 WinPE 映像中安装了 WinPE-NetFX 包，OpenFileDialog 在 WinPE 中也不可用，并且尝试使用它会引发问题中引用的错误。这些使用非托管 GetOpenFileName 函数的 OpenFileDlg 示例是我能够找到的在 WinPE 中使用的唯一替代方案。