Using RAD Studio, the following procedure creates a modal form at design time that is displayed later during program execution.  

Building this VCL application consists of the following steps:

1. Create the project directory.
2. Create two forms for the project.
3. Link the forms.
4. Create a control on the main form to display the modal form; then write the event handler.
5. Build and run the application.

1. Choose FileNewOtherDelphi Projects or C++Builder Projects and double-click the VCL Forms Application icon. The VCL Forms Designer displays Form1.
2. Choose FileNewOtherDelphi ProjectsDelphi Files or FileNewOtherC++Builder Files and double-click the Form icon. The VCL Forms Designer displays Form2.

1. For Delphi, select Form1 and choose FileUse Unit. For C++, select Form1 and choose FileInclude Unit Hdr. The Uses Unit dialog displays.
2. Select Form2 (the form that Form1 needs to reference) in the dialog.
3. Click OK.

For C++, the #include “Unit2.h” directive is added to Unit1.h.

1. Select Form1, if necessary; then, from the Standard page of the Tool Palette, place a button on the form.
2. In the Object Inspector with Button1 selected, double-click the OnClick event on the Events tab. The Code Editor displays with the cursor in the TForm1.Button1Click (Delphi) or TForm1::Button1Click (C++) event handler block.
3. Enter the following event handling code:

Form2.ShowModal;

Form2–>ShowModal();

1. Save all files in the project; then choose RunRun. The application executes, displaying Form1.
2. Click the button. Form2 displays.
3. Click the X in the upper right corner of Form2. Form2 closes and Form1 becomes the active form.