◆◆主程序调用DLL中的非模式窗口，怎样才能让这个非模式窗口自己关闭，并释放掉DLL，而不是从主窗口使其关闭◆◆(50分)

主程序以动态引入的方式调用DLL，并打开DLL中的一个非模式窗口。我现在想通过点击这个<br>非模式窗口右上角的关闭按钮（也就是那个“X”按钮）将非模式窗口自己关闭，并释放资源，<br>并使得主程序释放掉DLL。请问应该怎么做？谢谢！（最好是给出代码）<br>

自up

难道没人帮我吗？[]

主程序调用DLL时将自己的句柄用参数方式传给DLL,<br>然后窗口结束时可以发送自定义消息给主程序。<br>主窗口接到消息后就释放DLL。

谢谢DarwinZhang大哥，我按照你的思路做了，但是又遇到新的问题啦，就是DLL中的窗口关闭了，<br>可主程序也跟着关闭了，你帮我看看，到底是怎么回事，我把代码贴出来。<br>//主程序代码<br>unit MainForm;<br><br>interface<br><br>uses<br>&nbsp; Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,<br>&nbsp; StdCtrls, AppEvnts;<br><br>type<br>&nbsp; TShowForm = function(AHandle: THandle; UniqueMsgID: Cardinal): THandle; stdcall;<br>&nbsp; TCloseForm = procedure(FormHandle: THandle); stdcall;<br><br>&nbsp; TfrmMain = class(TForm)<br>&nbsp; &nbsp; Button1: TButton;<br>&nbsp; &nbsp; Button2: TButton;<br>&nbsp; &nbsp; procedure Button1Click(Sender: TObject);<br>&nbsp; &nbsp; procedure Button2Click(Sender: TObject);<br>&nbsp; &nbsp; procedure FormCreate(Sender: TObject);<br>&nbsp; private<br>&nbsp; &nbsp; { Private declarations }<br>&nbsp; &nbsp; UniqueMsgID: Cardinal;<br>&nbsp; &nbsp; DLLHandle, FormHandle: THandle; //DLL的地址，要显示的Form的句柄<br>&nbsp; &nbsp; ShowForm: TShowForm;<br>&nbsp; &nbsp; CloseForm: TCloseForm;<br>&nbsp; public<br>&nbsp; &nbsp; { Public declarations }<br>&nbsp; &nbsp; procedure WndProc(var Msg: TMessage); override;<br>&nbsp; end;<br><br>var<br>&nbsp; frmMain: TfrmMain;<br><br>implementation<br><br>{$R *.DFM}<br><br>procedure TfrmMain.Button1Click(Sender: TObject);<br>begin<br>&nbsp; { 动态调用的过程 }<br>&nbsp; if DLLHandle = 0 then<br>&nbsp; begin<br>&nbsp; &nbsp; DLLHandle := LoadLibrary('TestDLL.dll');<br>&nbsp; &nbsp; try<br>&nbsp; &nbsp; &nbsp; if DLLHandle = 0 then<br>&nbsp; &nbsp; &nbsp; &nbsp; raise Exception.Create('装入动态链接库DLLFile.dll失败！');<br>&nbsp; &nbsp; &nbsp; { 在这里，将本次要用到的例程全部引入。对于某些必须成功装入的例程来说，如果<br>&nbsp; &nbsp; &nbsp; &nbsp; 装入失败，则立即释放DLL }<br>&nbsp; &nbsp; &nbsp; @ShowForm := GetProcAddress(DLLHandle, 'ShowForm');<br>&nbsp; &nbsp; &nbsp; if @ShowForm = nil then<br>&nbsp; &nbsp; &nbsp; &nbsp; Abort;<br>&nbsp; &nbsp; &nbsp; @CloseForm := GetProcAddress(DLLHandle, 'CloseForm');<br>&nbsp; &nbsp; &nbsp; if @CloseForm = nil then<br>&nbsp; &nbsp; &nbsp; &nbsp; Abort;<br>&nbsp; &nbsp; &nbsp; FormHandle := ShowForm(Application.Handle, UniqueMsgID);<br>&nbsp; &nbsp; except<br>&nbsp; &nbsp; &nbsp; FreeLibrary(DLLHandle);<br>&nbsp; &nbsp; &nbsp; DLLHandle := 0;<br>&nbsp; &nbsp; end;<br>&nbsp; end;<br>end;<br><br>procedure TfrmMain.Button2Click(Sender: TObject);<br>begin<br>&nbsp; if DLLHandle &lt;&gt; 0 then<br>&nbsp; begin<br>&nbsp; &nbsp; CloseForm(FormHandle);<br>&nbsp; &nbsp; FreeLibrary(DLLHandle);<br>&nbsp; &nbsp; DLLHandle := 0;<br>&nbsp; end;<br>end;<br><br>procedure TfrmMain.FormCreate(Sender: TObject);<br>begin<br>&nbsp; DLLHandle := 0;<br>&nbsp; UniqueMsgID := RegisterWindowMessage('shiwei is a girl 10:50:20');<br>end;<br><br>procedure TfrmMain.WndProc(var Msg: TMessage);<br>begin<br>&nbsp; if Msg.Msg = UniqueMsgID then<br>&nbsp; &nbsp; if DLLHandle &lt;&gt; 0 then<br>&nbsp; &nbsp; begin<br>&nbsp; &nbsp; &nbsp; CloseForm(FormHandle);<br>&nbsp; &nbsp; &nbsp; FreeLibrary(DLLHandle);<br>&nbsp; &nbsp; &nbsp; DLLHandle := 0;<br>&nbsp; &nbsp; end;<br>&nbsp; inherited WndProc(Msg);<br>end;<br><br>end.<br>//-----------------------------------------------------------------------------<br>//DLL单元代码<br>unit NonModalForm;<br><br>interface<br><br>uses<br>&nbsp; Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs;<br><br>type<br>&nbsp; TfrmNonModal = class(TForm)<br>&nbsp; private<br>&nbsp; &nbsp; { Private declarations }<br>&nbsp; &nbsp; procedure WMSysCommand(var Msg: TWMSysCommand); message WM_SYSCOMMAND;<br>&nbsp; public<br>&nbsp; &nbsp; { Public declarations }<br>&nbsp; end;<br><br>function ShowForm(AHandle: THandle; UniqueMsgID: Cardinal): THandle; stdcall;<br>procedure CloseForm(FormHandle: THandle); stdcall;<br><br>exports<br>&nbsp; ShowForm, CloseForm;<br><br>var<br>// &nbsp;frmNonModal: TfrmNonModal;<br>&nbsp; UniMsgID: Cardinal;<br>//var<br>&nbsp; FormHandle: THandle;<br><br>implementation<br><br>{$R *.DFM}<br><br>function ShowForm(AHandle: THandle; UniqueMsgID: Cardinal): THandle;<br>begin<br>&nbsp; Application.Handle := AHandle;<br>&nbsp; UniMsgID := UniqueMsgID;<br>&nbsp; FormHandle := THandle(TfrmNonModal.Create(Application));<br>&nbsp; Result := FormHandle; //将新建窗体的句柄返回给主程序<br>&nbsp; with TfrmNonModal(FormHandle) do<br>&nbsp; try<br>&nbsp; &nbsp; Show;<br>&nbsp; except<br>&nbsp; &nbsp; Free;<br>&nbsp; &nbsp; Result := 0;<br>&nbsp; end;<br>end;<br><br>procedure CloseForm(FormHandle: THandle);<br>begin<br>&nbsp; if FormHandle &lt;&gt; 0 then //FormHandle &lt;&gt; 0，表示已经建立的实例，则可以执行关闭、释放<br>&nbsp; begin<br>&nbsp; &nbsp; with TfrmNonModal(FormHandle) do<br>&nbsp; &nbsp; begin<br>&nbsp; &nbsp; &nbsp; Close;<br>&nbsp; &nbsp; &nbsp; Free;<br>&nbsp; &nbsp; end;<br>&nbsp; end;<br>end;<br><br>{ TfrmNonModal }<br><br>procedure TfrmNonModal.WMSysCommand(var Msg: TWMSysCommand);<br>begin<br>&nbsp; if Msg.CmdType = SC_CLOSE then<br>&nbsp; &nbsp; SendMessage(HWND_BROADCAST, UniMsgID, 0, 0)<br>&nbsp; else<br>&nbsp; &nbsp; inherited;<br>end;<br><br>end.

是不是因为在<br>function ShowForm(AHandle: THandle; UniqueMsgID: Cardinal): THandle;<br>begin<br>&nbsp; Application.Handle := AHandle;<br>.....这个函数里把DLL的Application指向了EXE主程序的Handle，而在退出DLL时<br>没有把DLL 的Application恢复过来？？ 呵呵，我也不懂。你的这个DLL和EXE的调用<br>和实现我学了很多东西。谢谢！

wqthai：<br>&gt;&gt;而在退出DLL时没有把DLL 的Application恢复过来？？<br>为什么要恢复过来呢？没有必要啊！

&nbsp;UniqueMsgID := RegisterWindowMessage('shiwei is a girl 10:50:20');<br>在2000下运行时没注册成功<br><br>

我看过别人的调用DLL窗体的过程：<br>Library单元的初始化部分先执行自定义的DLLProc<br>begin<br>&nbsp; DLLProc := @DLLEnterPoint;<br>&nbsp; DllEnterPoint(DLL_PROCESS_ATTACH);<br>&nbsp; DLLHandle := Application.Handle; &nbsp;//保存DLL的Application的Handle<br>end.<br><br>而DLLProc定义为：<br>procedure DllEnterPoint(dwReason: DWORD);<br>dwReason参数有四种类型：<br>DLL_PROCESS_ATTACH:进程进入时<br>DLL_PROCESS_DETACH进程退出时<br>DLL_THREAD_ATTACH 线程进入时<br>DLL_THREAD_DETACH 线程退出时<br>if dwReason = DLL_PROCESS_ATTACH then<br>&nbsp; Application.Handle := DLLHandle; &nbsp;//恢复<br><br>具体说我也不晓得此Application与Dll中的Application都有什么区别。<br>感觉如果不恢复过来，释放DLL时是不是将EXE的Application对象给Free掉了！<br>猜的。有没有高手给讲讲EXE和DLL的知识阿？<br>

jackyzhang：<br>成功了

是因为消息注册没有成功的原因？？

SENDMESSAGE是要等主程序处理完释放那段过程才返回，而那时DLL已经被释放掉了，所以程序出错了<br>不能用这种发送消息的办法！

wqthai：<br>我这里调用DLL时不需要做什么初始化工作，所以没有必要写入口函数和初始代码，完全是两回事！<br>至于Application.Handle := AHandle;<br>这是非常正确的！！！它的目的是使DLL中的窗体在建立时，指定主程序的Application对象为父，<br>这样做的好处很多，否则，比如：DLL窗体最小化，或DLL窗体还没被释放时，主程序被强行关闭等等很多<br>时候会带来不可预料的错误！<br>试想一下，平时的应用程序，在主窗口中动态创建一个子窗口，使其父为Application，这有错吗？？？<br>将它关闭时还要恢复什么东西吗？？<br>所以Application是绝对没有错的！！！！<br><br>现在，这个问题的80%我都做好了，只是在消息处理的问题上可能什么地方没处理正确，希望大家多多帮助！

&gt;&gt;SENDMESSAGE是要等主程序处理完释放那段过程才返回，而那时DLL已经被释放掉了，所以程序出错了<br>&gt;&gt;不能用这种发送消息的办法！<br>这话似乎说到点子上了，容我再看看

procedure TfrmMain.WndProc(var Msg: TMessage);<br>begin<br>&nbsp; if Msg.Msg = UniqueMsgID then<br>&nbsp; begin<br>&nbsp; &nbsp; if DLLHandle &lt;&gt; 0 then<br>&nbsp; &nbsp; begin<br>&nbsp; &nbsp; &nbsp; PostMessage(FrmMain.Handle,Wm_User+1,0,0);<br>&nbsp; &nbsp; end<br>&nbsp; end<br>&nbsp; else if Msg.Msg=Wm_User+1 then<br>&nbsp; &nbsp;if DllHandle&lt;&gt;0 then<br>&nbsp; &nbsp;begin<br>&nbsp; &nbsp; &nbsp; CloseForm(FormHandle);<br>&nbsp; &nbsp; &nbsp; FreeLibrary(DLLHandle);<br>&nbsp; &nbsp; &nbsp; DLLHandle := 0;<br>&nbsp; &nbsp;end;<br>&nbsp; inherited WndProc(Msg);<br>end;<br><br><br>好象这样没把内存全释放出来，在任务管理器中看到的每次都会增加内存10几K呢

把内存增加的问题解决好了就可以了！是4K到8K不等？

问题得以圆满解决！！<br>DarwinZhang首先提出用传递消息的方法，给10；<br>遂我马上写了上面的代码，但还有小问题，就是主程序也被关闭了，正在冥思苦想的时候，<br>jackyzhang提出是SendMessage的问题，非常正确！！！一语点醒梦中人啊！！！否则，我根本<br>就不王那里想，非常好！非常好！给30分！(当然，不仅仅是换成PostMessage就完了)。<br>wqthai虽然对我没有任何实质性的帮助，但鉴于积极参与，忙前忙后的，也给10分。<br>分数就这么少，如果分配得不合理，大家谅解！<br>再次感谢各位的大力帮忙！！！

jackyzhang：<br>&gt;&gt;把内存增加的问题解决好了就可以了！是4K到8K不等？<br>这是Windows的内存管理机制的问题，不是程序的问题，比如：数M的程序，一旦被最小化，通过<br>任务管理器一看，占用内存马上降到几百K。所以说，它显示的是不准确的。[]

但是不通过DLL调用的话，它释放，打开就不会增加，这是为什么呢？

to 小笨苯,<br>我也遇到这种问题,问后来你是怎么解决的