Below is an example that creates a new copy method for winedit object which copies the data from the text field to clipboard and then shows that data (which is copied to the clipboard) in a message box. In a new library file type:
Sub Copy (edit)
Edit.SetSelection 0, Len(Edit.GetROProperty("text"))
Edit.Type micCtrlDwn + "c" + micCtrlUp
RegisterUserFunc "WinEdit", "Copy","Copy"
Open a new test and type:
Dialog("text:=Login").winedit("attached text:=Agent Name:").Copy
unRegisterUserFunc "WinEdit", "Copy"
Associate the library with the test as we did earlier. Make sure 'Login' window is open (Start-> All Programs -> QuickTest Professional -> Sample Applications ->Flight). In this login window type "sachin" in the Agent Name text field and run the test.
For RegisterUserFunc and UnRegisterUserFunc please see the QTP user guide.
QTP Function Library
QTP Function Library - Example 1
QTP Function Library - Example 2
QTP Function Library - Example 3