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--- checkparametersbeforecreateform [2025/04/18 03:14] – created jwan
+++ checkparametersbeforecreateform [2025/10/10 10:15] (current) – external edit 127.0.0.1
@@ Line 69: / Line 69: @@
 How It Works:
-- Parameter Check in Main Block:- Before calling Application.CreateForm, the program checks if any parameters are provided using ParamCount.
+  * Parameter Check in Main Block:- Before calling Application.CreateForm, the program checks if any parameters are provided using ParamCount.
-- If /scan is passed as a parameter (case-insensitive), it shows a message and terminates the application using Halt.
+  * If /scan is passed as a parameter (case-insensitive), it shows a message and terminates the application using Halt.
-- If no parameters or a different parameter is passed, it proceeds to create and display the form.
+  * If no parameters or a different parameter is passed, it proceeds to create and display the form.
+  * Form Creation:- The form's constructor (Create) is overridden, but in this case, it doesn’t perform parameter checking (since it’s already handled in the main program block).
-- Form Creation:- The form's constructor (Create) is overridden, but in this case, it doesn’t perform parameter checking (since it’s already handled in the main program block).
+  * Graceful Exit with Message:- When /scan is detected, a message box informs the user, and the program exits without showing the form.
-- Graceful Exit with Message:- When /scan is detected, a message box informs the user, and the program exits without showing the form.
@@ Line 83: / Line 81: @@
+Additional option is what if no form will be created and just display a message in console, just add the $APPTYPE like this:
+<code>
+{$APPTYPE CONSOLE}
+program NetworkDownAlarm;
+uses
+  Forms,
+  mainnetdownalarm in 'mainnetdownalarm.pas' {formmain_networkdown};
+{$R *.res}
+begin
+  Application.Initialize;
+  if ParamCount > 0 then begin
+    if ParamStr(1)='/scan' then
+    begin
+      // If the parameter is "/scan", do not create the form and exit the program
+      writeln('Scan mode executed. No form will be created.');
+      Halt; // Terminate the program
+    end;
+  end;
+  Application.CreateForm(Tformmain_networkdown, formmain_networkdown);
+  Application.Run;
+end.
+</code>
+Another is to create different form base on the parameter:
+<code>
+program Project1;
+uses
+  Forms, Dialogs, SysUtils, Unit1 in 'Unit1.pas', Unit2 in 'Unit2.pas';
+{$R *.RES}
+const
+  ProgramVersion = '1.0.0'; // Define the program version
+begin
+  Application.Initialize;
+  // Check for command-line parameters
+  if ParamCount > 0 then
+  begin
+    if SameText(ParamStr(1), '/scan') then
+    begin
+      // If the parameter is "/scan", create and display TScanForm (Unit2)
+      Application.CreateForm(TScanForm, ScanForm);
+      Application.Run;
+      Exit;
+    end
+    else if SameText(ParamStr(1), '/help') then
+    begin
+      // If the parameter is "/help", show help text and exit
+      MessageBox(0, PChar('Program Version: ' + ProgramVersion + sLineBreak +
+                          'Usage:' + sLineBreak +
+                          '/scan - Run scan mode (no default form).' + sLineBreak +
+                          '/help - Display this help message.'),
+                          'Help', MB_ICONINFORMATION or MB_OK);
+      Halt; // Terminate the program
+    end;
+  end;
+  // If no parameters or unrecognized parameter, create and display TForm1
+  Application.CreateForm(TForm1, Form1);
+  Application.Run;
+end.
+</code>
+NOTE: just make sure each of the form will have:
+<code>
+public
+    { Public declarations }
+    constructor Create(AOwner: TComponent); override;
+constructor Tformmain.Create(AOwner: TComponent);
+begin
+   inherited Create(AOwner); // Call the inherited constructor
+end;
+</code>