Sending and getting ID

I print the dates, which I get from SQL in a Listbox. I have managed to control double-clicks (when I click on a date, dialog shows up). Now, I want to print detailed informations in that dialog, based on a date, which I double-clicked in a Listbox in main window...(I create a new SQL query, of course...)...

How can I send value of string in Listbox to a Dialog?

Thanks for help!

One possibility is to use either DialogBoxParam or CreateDialogParam to create your modal/modeless dialog; the last parameter of either function enables you to pass user defined data to the dialog which you can access as the lParam of the dialog's WM_INITDIALOG message.