Create an application that stores people's names and birthdays in a file (Fig. 23.40). The user creates a file and inputs each person's first name, lastname and birthday on the Form. The information is then written to the file.
a) Copying the template to your working directory. Copy the directory C: ExamplesTutorial23ExercisesBirthdaySaver to your C: SimplyVB2008 directory.
b) Opening the application's template file. Double click BirthdaySaver.sln in the
BirthdaySaver directory to open the application (Fig. 23.40).
c) Adding and customizing an OpenFileDialog component. Add an OpenFile Dialog component to the Form. Change its Name property to openFileDialog. Set the CheckFileExists property to False.
d) Importing namespace System. IO. Import System. IO to allow file processing.
e) Declaring a StreamWriter object. Declare a StreamWriter object that can be used throughout the entire class.
f) Defining the Open File... Button's Click event handler. Double click the Open File... Button to create the openButton_Click event handler. Write code to display the Open dialog. If the user clicks the Cancel Button in the dialog, the event handler performs no further actions. Otherwise, determine whether the user provided a file name that ends with the . txt extension. If not, display a MessageBox asking the user to select an appropriate file. If the user specified a valid file name, perform Step g.
g) Initializing the StreamWriter. Initialize the StreamWriter in the event handler openButton_Click, passing the user-input file name as an argument. Allow the user to append information to the file by passing the Boolean value True as the second argument to the StreamWriter. Enable the Enter and Close File Buttons. Disable the Open File... Button.
h) Defining the Enter Button's Click event handler. Double click the Enter Button to create the event handler enterButton_Click. This event handler writes the name of the person and the person's birthday on a line in the file. Finally, the TextBoxes on the Form are cleared, and the DateTimePicker's value is set back to the current date.
i) Defining the Close File Button's Click event handler. Double click the Close FileButton to create the closeButton_Click event handler. Close the StreamWriter connection and reset the Buttons to their initial state in this event handler.
j) Running the application. Select Debug > Start Debugging to run your application.
Open a file by clicking the Open File... Button. After a file has been opened, use the input fields provided to enter birthday information. After each person's name and birthday are typed in, click the Enter Button. When you are finished, close the file by clicking the Close File Button. Browse to the file and ensure that its contents contain the birthday information that you entered.
k) Closing the application. Close your running application by clicking its close box.
l) Closing the IDE. Close the Visual Basic IDE by clicking its close box.
The expert creates an application that stores people's names and birthdays in a file.