C#调用C++的DLL，并将其返回的Form.Handle嵌入C#的Control中显示

[zmy0611]

C#写的Form，要求能调用C++的DLL(API), 在API中创建一个C++的Form，返回C++.Form.Handle嵌入到C#的Form中显示
目前已能显示，但只要改变C#Form的Size，就当机，高手看看哪里写错了：
C#代码如下：

/// <summary>
/// Summary description for Form1.
/// </summary>
public class Form1 : System.Windows.Forms.Form
{
	private ApplicationControl applicationControl1;
	private IContainer components;
	public Form1()
	{
		InitializeComponent();
	}
	/// <summary>
	/// Clean up any resources being used.
	/// </summary>
	protected override void Dispose( bool disposing )
	{
		if( disposing )
		{
			if (components != null) 
			{
				components.Dispose();
			}
		}
		base.Dispose( disposing );
	}
	#region Windows Form Designer generated code	private void InitializeComponent()
	{
		this.applicationControl1 = new ApplicationControl();
		this.SuspendLayout();
		// 
		// applicationControl1
		// 
		this.applicationControl1.Dock = System.Windows.Forms.DockStyle.Fill;
		this.applicationControl1.Location = new System.Drawing.Point(0, 0);
		this.applicationControl1.Name = "applicationControl1";
		this.applicationControl1.Size = new System.Drawing.Size(447, 328);
		this.applicationControl1.TabIndex = 0;
		// 
		// Form1
		// 
		this.AutoScaleBaseSize = new System.Drawing.Size(6, 14);
		this.ClientSize = new System.Drawing.Size(447, 328);
		this.Controls.Add(this.applicationControl1);
		this.Name = "Form1";
		this.Text = "Form1";
		this.ResumeLayout(false);
	}
	#endregion
	[STAThread]
	static void Main() 
	{
		Application.Run(new Form1());
	}
}
public class ApplicationControl : System.Windows.Forms.Panel
{
	bool created = false;
	IntPtr appWin;
	public ApplicationControl()
	{			
	}
	[DllImport("user32.dll", EntryPoint="GetWindowThreadProcessId",  SetLastError=true,
		 CharSet=CharSet.Unicode, ExactSpelling=true,
		 CallingConvention=CallingConvention.StdCall)]
	private static extern long GetWindowThreadProcessId(long hWnd, long lpdwProcessId); 
	[DllImport("user32.dll", SetLastError=true)]
	private static extern IntPtr FindWindow (string lpClassName, string lpWindowName);
	[DllImport("user32.dll", SetLastError=true)]
	private static extern long SetParent (IntPtr hWndChild, IntPtr hWndNewParent);
	[DllImport("user32.dll", EntryPoint="GetWindowLongA", SetLastError=true)]
	private static extern long GetWindowLong (IntPtr hwnd, int nIndex);
	[DllImport("user32.dll", EntryPoint="SetWindowLongA", SetLastError=true)]
	private static extern long SetWindowLong (IntPtr hwnd, int nIndex, long dwNewLong);
	[DllImport("user32.dll", SetLastError=true)]
	private static extern long SetWindowPos(IntPtr hwnd, long hWndInsertAfter, long x, long y, long cx, long cy, long wFlags);
	[DllImport("user32.dll", SetLastError=true)]
	private static extern bool MoveWindow(IntPtr hwnd, int x, int y, int cx, int cy, bool repaint);
	[DllImport("user32.dll", EntryPoint="PostMessageA", SetLastError=true)]		
	private static extern bool PostMessage(IntPtr hwnd, uint Msg, long wParam, long lParam);
	private const int SWP_NOOWNERZORDER = 0x200;
	private const int SWP_NOREDRAW = 0x8;
	private const int SWP_NOZORDER = 0x4;
	private const int SWP_SHOWWINDOW = 0x0040;
	private const int WS_EX_MDICHILD = 0x40;
	private const int SWP_FRAMECHANGED = 0x20;
	private const int SWP_NOACTIVATE = 0x10;
	private const int SWP_ASYNCWINDOWPOS = 0x4000;
	private const int SWP_NOMOVE = 0x2;
	private const int SWP_NOSIZE = 0x1;
	private const int GWL_STYLE = (-16);
	private const int WS_VISIBLE = 0x10000000;
	private const int WM_CLOSE = 0x10;
	private const int WS_CHILD = 0x40000000;
	/// <summary>
	/// 控件尺寸改变时重绘
	/// </summary>
	/// <param name="e">Not used</param>
	protected override void OnSizeChanged(EventArgs e)
	{
		this.Invalidate();
		base.OnSizeChanged(e);
	}
	/// <summary>
	/// Creeate control when visibility changes
	/// </summary>
	/// <param name="e">Not used</param>
	protected override void OnVisibleChanged(EventArgs e)
	{
		if (!created)
		{
			created = true;
			appWin = IntPtr.Zero;
			try
			{
				//调用DLL的API并嵌入C#的Form
				DllInvoke _DllInvoke = new DllInvoke(Application.StartupPath + @"\Project.dll");
				TestCallDelegate TestCall = (TestCallDelegate)_DllInvoke.Invoke("TestCall", typeof(TestCallDelegate));
				appWin = TestCall();
				/* 调用Exe并嵌入C#的Form方式
				Process p = System.Diagnostics.Process.Start("Exe路径");
				p.WaitForInputIdle();
				appWin = p.MainWindowHandle;*/
			}
			catch (Exception ex)
			{
				MessageBox.Show(this, ex.Message, "Error");
			}
			// Put it into this form
			SetParent(appWin, this.Handle);
			// Remove border and whatnot
			SetWindowLong(appWin, GWL_STYLE, WS_VISIBLE);
			// Move the window to overlay it on this window
			MoveWindow(appWin, 0, 0, this.Width, this.Height, true);
		}
		base.OnVisibleChanged (e);
	}
	/// <summary>
	/// 控件销毁时关闭C++的FORM
	/// </summary>
	/// <param name="e"></param>
	protected override void OnHandleDestroyed(EventArgs e)
	{
		// Stop the application
		if (appWin != IntPtr.Zero)
		{
			// Post a colse message
			PostMessage(appWin, WM_CLOSE, 0, 0);
			System.Threading.Thread.Sleep(1000);
			// Clear internal handle
			appWin = IntPtr.Zero;
		}
		base.OnHandleDestroyed (e);
	}
	/// <summary>
	/// Update display of the executable
	/// </summary>
	/// <param name="e">Not used</param>
	protected override void OnResize(EventArgs e)
	{
		if (this.appWin != IntPtr.Zero)
		{
			MoveWindow(appWin, 0, 0, this.Width, this.Height, true);
		}
		base.OnResize (e);
	}
}
public delegate IntPtr TestCallDelegate();
/// <summary>
/// 动态调用Dll
/// </summary>
public class DllInvoke
{
	[DllImport("kernel32.dll")]
	private extern static IntPtr LoadLibrary(string path);
	[DllImport("kernel32.dll")]
	private extern static IntPtr GetProcAddress(IntPtr lib, string funcName);
	[DllImport("kernel32.dll")]
	private extern static bool FreeLibrary(IntPtr lib);

	private IntPtr hLib;
	public DllInvoke(String DLLPath)
	{
		hLib = LoadLibrary(DLLPath);
	}
	~DllInvoke()
	{
		FreeLibrary(hLib);
	}
	/// <summary>
	/// 将要执行的函数转换为委托
	/// </summary>
	/// <param name="APIName"></param>
	/// <param name="t"></param>
	/// <returns></returns>
	public Delegate Invoke(string APIName, Type t)
	{
		IntPtr api = GetProcAddress(hLib, APIName);
		return (Delegate)Marshal.GetDelegateForFunctionPointer(api, t);
	}
}

C++代码如下：(生成Project.Dll, 放在C#项目的Debug下供调用)

Unit1.h:
class TForm1 : public TForm
{
	__published:
	private:
	public:
};

Unit1.cpp
//---------------------------------------------------------------------------
#include <vcl.h>
#pragma hdrstop
#include "Unit1.h"
//---------------------------------------------------------------------------
#pragma package(smart_init)
#pragma resource "*.dfm"
extern "C" __declspec(dllexport) WINAPI HWND TestCall()
{
        TForm1 *f = new TForm1(NULL);
        f->Visible = true;
        return f->Handle;
}
//---------------------------------------------------------------------------
__fastcall TForm1::TForm1(TComponent* Owner)
        : TForm(Owner)
{
}

[sdl2005lyx]

2、CView模式
这个要复杂些：
void OpenVQCRun(CWnd* pWnd) //注意：这里比上面多个参数
{
CRuntimeClass *pViewClass=RUNTIME_CLASS(CVQCRunFrmView );
CCreateContext *pContext=new CCreateContext;
pContext->m_pCurrentDoc=NULL;
pContext->m_pCurrentFrame=NULL;
pContext->m_pLastView=NULL;
pContext->m_pNewDocTemplate=NULL;
pContext->m_pNewViewClass=pViewClass;

CWnd *pTempWnd=DYNAMIC_DOWNCAST(CWnd,pViewClass->CreateObject());
pTempWnd->Create(NULL,NULL,WS_CHILD ,CRect(0,0,725,660),
pWnd,IDD_VQC_RUN_VIEW,pContext); //注意这里的View大小要跟你实际大小一样
delete pContext;
CView* pView=DYNAMIC_DOWNCAST(CVQCRunFrmView ,pTempWnd);
pView->OnInitialUpdate();
pView->ShowWindow(SW_SHOW);
}

同样再建立新的Dialog的工程：


BOOL CVQCRunDlg::OnInitDialog()
{
CDialog::OnInitDialog();

// Add "About..." menu item to system menu.

// IDM_ABOUTBOX must be in the system command range.
ASSERT((IDM_ABOUTBOX & 0xFFF0) == IDM_ABOUTBOX);
ASSERT(IDM_ABOUTBOX < 0xF000);

CMenu* pSysMenu = GetSystemMenu(FALSE);
if (pSysMenu != NULL)
{
CString strAboutMenu;
strAboutMenu.LoadString(IDS_ABOUTBOX);
if (!strAboutMenu.IsEmpty())
{
pSysMenu->AppendMenu(MF_SEPARATOR);
pSysMenu->AppendMenu(MF_STRING, IDM_ABOUTBOX, strAboutMenu);
}
}

// Set the icon for this dialog. The framework does this automatically
// when the application's main window is not a dialog
SetIcon(m_hIcon, TRUE); // Set big icon
SetIcon(m_hIcon, FALSE); // Set small icon

// TODO: Add extra initialization here
OpenVQCRun(this); //注意，函数的位置跟上面的不一样
return TRUE; // return TRUE unless you set the focus to a control
}

[zmy0611]

几个dll改过来还可以，关键现在公司C++的DLL有上千支，
并且用Dll方式时，是可以实现资料库连接共享的
做成独立exe的话，每运行一个exe都要产生独自的资料库连接
最主要的原因还是DLL太多，并且DLL不归我管，没有说的过去的理由不可能让别人改DLL

[sdl2005lyx]

你还是没理解我的意思，针对你来说，你只是用几个dll，你也可以不用改变原来的dll，直接在exe工程里，加入那几行代码而已！

[sdl2005lyx]

其实，我也正在做C#改造VC界面的事情，一般的原则：
1、对于较简单的界面，如登录，简单对话框，数据框等，尽量用C#Form重写，以便风格统一。
2、对于比较复杂的界面，特殊是这些工程有涉及到比较复杂的算法，在C#这边一时难以改造，而且有可能对原来的算法或流程理解错误，那只有退而求其次，把少数的dll封装成独立的dll，在C#这边进程调用，难看点而已！



不知LZ是否也是在做类似的事情。。。。

[zmy0611]

你的意思是用C++写个exe，通过传入参数的方式调用不同的dll显示C++的Form。
然后在C#中用Process调用这个exe？

[zmy0611]

这样是可以，但资料库连接等就得每个Process都是独立的了。

[zmy0611]

不会吧，没高手进来看看，我顶，大家帮顶啊

[confidenceyu]

没试过，顶

[zmy0611]

谢谢你顶，再顶上去，我就不信没人会的

[sdl2005lyx]

建议LZ换个思路：C#调用C++的dll(功能)，可以采取互操作的办法；如果要调C++的界面，最好不要通过dll的方式new出来。原因：
1、C++与C#的界面风格完全不同，强制揉合在一起，很别扭；
2、两者响应事件，改变窗体背景、大小、字体、颜色等方式都不相同；

解决办法：
1、用C#重写C++界面；
2、把C++界面封装成独立的exe供C#进程调用

[以专业开发人员为伍]

要强行从底层修改一个组件，应该先搞懂原理上是否真的可行再说。强行破坏一个组件，你倒是显示了，不是也宕机了嘛。

你的领导有没有承受“经过论证发觉完全错误”的心理准备呢？如果没有，我建议你赶紧退，把c++的界面处理程序扫到字纸篓里。

[卧_槽]

把这个组件写成com。

[jian03112]

用C++的ATL写成COM组件的形式，这样就好调用了，直接把COM包引进来就能直接用了，仅供参考。

[jian03112]

不用COM 也可以，平台调用P-INVOKE 参考
http://tech.ddvip.com/2010-09/1283763341159872_2.html

[zmy0611]

找到原因了，原来是因为:
DllInvoke _DllInvoke = new DllInvoke(Application.StartupPath + @"\Project.dll");

_DllInvoke应该定义为全局变量，否则离开这个函数就会被GC回收，而
DllInvoke 的析构中又FreeLibrary了，当然会当机

[sdl2005lyx]

解决就好。。。^_^

[feng9330]

mark

[sdl2005lyx]

是的，这样改造工作最少，原来的流程、算法都能沿用。。。

[zmy0611]

[Quote=引用 15 楼 sdl2005lyx 的回复:]

是的，这样改造工作最少，原来的流程、算法都能沿用。。。
[/Quote]

如果我就想用DLL，你能有解决方案吗？那些个领导会觉得：每个Process的数据库连接不能共享肯定不好的

[zmy0611]

sdl2005lyx， 奇怪了，我自己用CB创建的exe竟然不能嵌入C#的Form。而换成notepad.exe就行

难道exe文件也有特殊需求才行？