Calling a form from another form

[Void]

Managed C++ does not let you call a form by its form name. In C# you can do formname.function if it is a public function. You can call a perform click in C# just by the formname. In managed c++ it is a little different.

I had to write a callback function that sends messages just to call a previous form. Here is the code:

At the header I inserted:

//#include <windows.h>    // You could theoretically include Windows.h to get
                                     // all of the WM_ message values, but then your
                                     // basic .NET objects like MessageBox would no longer
                                     // function without a series of #ifndefs.

// Define WM_USER using the value in windows.h
#define WM_USER 0x0400
#define WM_PLAY 0x0401
#define WM_STOP 0x0402
#define WM_RESTART 0x0403
#define WM_PAUSE 0x0404
#define WM_EXITME 0x0405

// Define our custom message
#define MSG_CHILDTEXT (WM_USER+1) // Nothing
#define MSG_CHILDPLAY (WM_PLAY+1)
#define MSG_CHILDSTOP (WM_STOP+1)
#define MSG_CHILDRESTART (WM_RESTART+1)
#define MSG_CHILDPAUSE (WM_PAUSE+1)
#define MSG_CHILDEXIT (WM_EXITME+1)

Declare this in the new form (child form)

public: System::Windows::Forms::NativeWindow^ m_nwndParent;

Assign a handle in the parent form

//myFullTrans->StartClick = ionTimer::Form1::childForm_StartClick();
			 myFullTrans->m_nwndParent = gcnew System::Windows::Forms::NativeWindow ();
			 myFullTrans->m_nwndParent->AssignHandle (this->Handle);

Create a functino in the new form

private: System::Void msgToParentForm(int m)
		 {
			 				// Create a new windows message object
			   System::Windows::Forms::Message msgTextSetter;

			   // Set the message type to our custom message
			   msgTextSetter.Msg = m;

			   // Tell the NativeWindow object to send the message
			   // to the default WndProc of the window whose handle
			   // it represents
			   m_nwndParent->DefWndProc (msgTextSetter);
		 }

Call the function

msgToParentForm(MSG_CHILDPAUSE);

[Void]

Now, you have to handle the callbacks in the parent form

		////////////////////////////////////////////////////////////
		// Override to get messages from child
		//////////////////////////////////////////////////////////
public: virtual System::Void WndProc(System::Windows::Forms::Message % message) override
		{
			try {
				switch (message.Msg)
				   {
					  // Handle our incoming custom message
					  case MSG_CHILDTEXT:
					  {
						 // This custom message should set the text of the parent's
						 // main textbox
						 break;
					  }
					  // Start the Timer - Run
					  case MSG_CHILDPLAY:
					  {
						  toolStripButton1_Click(nullptr,nullptr);
						  break;
					  }
					  case MSG_CHILDSTOP:	  
					  {
						stopBtn_Click(nullptr,nullptr);
						break; 
					  }
					  case MSG_CHILDRESTART:
					  {
						  restartBtn_Click(nullptr,nullptr);
						  break;
					  }
					  case MSG_CHILDPAUSE:
					  {
						  pauseBtn_Click(nullptr,nullptr);
						  break;
					  }
					  case MSG_CHILDEXIT:
					  {
						  myFullTrans->Close();
						  this->Close();
						  break;
					  }

					  // All other messages should be sent to the default WndProc
					  // for System::Windows::Forms
					  default:
					  {
						 Form::WndProc (message);
						 break;
					  }
				   
				   } // End Case
			}
			catch (System::Exception^)
			{
				MessageBox::Show("Error");
			}
					
		}

Change the message code to whatever you like and enjoy!