private void btnValidate_Click(object sender, RoutedEventArgs e) { double gpa; int streetnumber; int zipcode; if (txtFirstName.Text != "" && txtLastName.Text != "" && txtMajor.Text != "" && txtGPA.Text != "" && txtStreetNumber.Text != "" && txtStreetName.Text != "" && txtCity.Text != "" && txtState.Text != "" && txtZipCode.Text != "") { if (Double.TryParse(txtGPA.Text, out gpa) == true && Int32.TryParse(txtStreetNumber.Text, out streetnumber) == true && Int32.TryParse(txtZipCode.Text, out zipcode) == true) { gpa = Convert.ToDouble(txtGPA.Text); streetnumber = Convert.ToInt32(txtStreetNumber.Text); zipcode = Convert.ToInt32(txtZipCode.Text); Student student = new Student(); student.FirstName = txtFirstName.Text; student.LastName = txtLastName.Text; student.Major = txtMajor.Text; student.GPA = gpa; student.SetAddress(streetnumber, txtStreetName.Text, txtState.Text, txtCity.Text, zipcode); lstInfo.Items.Add(student); } else { if (Double.TryParse(txtGPA.Text, out gpa) == false) { MessageBox.Show("The GPA you entered is not a valid double."); } if (Int32.TryParse(txtStreetNumber.Text, out streetnumber) == false) { MessageBox.Show("The Street Number you entered is not a valid integer."); } if (Int32.TryParse(txtZipCode.Text, out zipcode) == false) { MessageBox.Show("The Zip Code you entered is not a valid integer."); } } } else { if (txtFirstName.Text == "") { MessageBox.Show("You did not enter a First Name."); } if (txtLastName.Text == "") { MessageBox.Show("You did not enter a Last Name."); } if (txtMajor.Text == "") { MessageBox.Show("You did not enter a Major."); } if (txtGPA.Text == "") { MessageBox.Show("You did not enter a GPA."); } if (txtStreetNumber.Text == "") { MessageBox.Show("You did not enter a Street Number."); } if (txtStreetName.Text == "") { MessageBox.Show("You did not enter a Street Name."); } if (txtCity.Text == "") { MessageBox.Show("You did not enter a City."); } if (txtState.Text == "") { MessageBox.Show("You did not enter a State."); } if (txtZipCode.Text == "") { MessageBox.Show("You did not enter a Zip Code."); } } }