How to automaticaly connect client to server

I am making a server-client program in which I have a main window. when i press a client button , client dialog should open up. In client window i dont want a connect or send button to connect to server instead i want that when my client dialog opens up & it automatically connects to server. I dont know how to write a signal-slot statement for this. please help.

In the constructor of your dialog, emit a signal, or directly send to some data to the client.
If you also want to send something when showing the dialog, reimplement the relevant event and emit a signal or send the data directly.