Question

Sir,
I created a MDI Parent form and three Mdi Child forms. Each child form contains a button. on clicking the button a new form is displayed. Mean to say if I click all the 3 buttons in 3 child form then there will be 3 new forms displayed. Its Fine.

My problems are :

1- Each new form which is displayed on clicking the button is also shown in the taskbar. I want each new form(apart from mdi child form) to be the mdi child of the main mdi parent.

2- These new forms diaplay the data received from the device connected via serialport. How many serialport objects I must create? If one, then where it must be created, on the Main mdi parent form or on the individual forms(3 new forms) ? If it is on the MDI parent form then how can i access that object in the 3 newly opened forms? If it is on the newly created forms then there would be 3 serialport objects accessing the same COM port which will result an Exception stating- “COM port is not accessible”.

PLease reply… I am recently passed out graduate and new in c#. SO please reply so that i can undrstand properly.
Thanks….

Answer 1

1) Every new Form has a bool property ShowInTaskbar – set it to false

// Create new MDI Child
// within ButtonClick in MainForm
CHILDFORMCLASS nf = new CHILDFORMCLASS();
nf.mdiParent = this;
nf.Show();

2) SerialPort Object – I would only create one in the main form
In your ChildForms you may access the mainForm by using MdiParent

MainForm
     Write a public property to access the serialPort

ChildForm
     PARENTFORMCLASS p = (PARENTFORMCLASS) this.Mdiparent;
     p.PUBLICPROPERTY // to access serial port object

3) as there is only one object – should no longer occur

hth