Set a Path to save file

Question

Hi all i need another help i.e i am using a sample code to save the data from the text boxes to a text file and i am saving it in to a directory. This one i hard coded to save the text file. Now i need to save it in a particular directory that user sets. Like i will opt him an option like preferences in menu there he can set a path to save his file and i would like to save the files in that path he created . How can i handle this any idea please. And also if he changes the directory i would like to move all the files to that drive he opted.

Thanks in advance...