DDX_ManagedControl calls CWinFormsControl::CreateManagedControl to create a control matching the resource control ID. If you use DDX_ManagedControl for a CWinFormsControl control (in wizard-generated code), you should not call CreateManagedControl explicitly for the same control.

Call DDX_ManagedControl in CWnd::DoDataExchange to create controls from resource IDs. For data exchange, you do not need to use the DDX/DDV functions with Windows Forms controls. Instead, you can place code to access the properties of the managed control in the DoDataExchange method of your dialog (or view) class, as in the following example.

The following example shows how to bind a native C++ string to a .NET user control.

Example

The following is an example of DDX/DDV data binding of an MFC string m_str with the user-defined NameText property of a .NET user control.

The control is created when CDialog::OnInitDialog calls CMyDlg::DoDataExchange for the first time, so any code that references m_UserControl must come after the DDX_ManagedControl call.

You can implement this code in the MFC01 application you created in How to: Create the User Control and Host in a Dialog Box.

Put the following code in the declaration of CMFC01Dlg:

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class CMFC01Dlg : public CDialog { CWinFormsControl<WindowsControlLibrary1::UserControl1> m_MyControl; CString m_str; };

Put the following code in the implementation of CMFC01Dlg:

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void CMFC01Dlg::DoDataExchange(CDataExchange* pDX) { CDialog::DoDataExchange(pDX); DDX_ManagedControl(pDX, IDC_CTRL1, m_MyControl); if (pDX->m_bSaveAndValidate) { m_str = m_MyControl->textBox1->Text; } else { m_MyControl->textBox1->Text = gcnew System::String(m_str); } }

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void CMFC01Dlg::DoDataExchange(CDataExchange* pDX)
{
   CDialog::DoDataExchange(pDX);
   DDX_ManagedControl(pDX, IDC_CTRL1, m_MyControl);

   if (pDX->m_bSaveAndValidate) {
      m_str = m_MyControl->textBox1->Text;
   } else
   {
      m_MyControl->textBox1->Text = gcnew System::String(m_str);
   }
}

Now we will add the handler method for a click on the OK button. Click the Resource View tab. In Resource View, double-click on IDD_MFC01_DIALOG. The dialog resource appears in Resource Editor. Then double click the OK button..

Define the handler as follows.

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void CMFC01Dlg::OnBnClickedOk() { AfxMessageBox(CString(m_MyControl.GetControl()->textBox1->Text)); OnOK(); }

And add the following line to the implementation of BOOL CMFC01Dlg::OnInitDialog().

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m_MyControl.GetControl()->textBox1->Text = "hello";

You can now build and run the application. Notice that any text in the text box will be displayed in a pop-up message box when the application closes.

Example

See Also

Reference