private async void ContentDialog_PersonName_TextChanged()

in FamilyNotes/AppDialogs/AddPersonContentDialog.xaml.cs [140:180]

• 30 lines of code
• 4 McCabe index (conditional complexity)

        private async void ContentDialog_PersonName_TextChanged(object sender, TextChangedEventArgs e)
        {
            // Make sure that our name exists
            if (String.IsNullOrWhiteSpace(PersonName.Text))
            {
                this.IsPrimaryButtonEnabled = false;
                textBlock.Text = "Please enter a user name.";
                return;
            }

            // Make sure the name if valid - we can check the directory since each person has a local directory

            IStorageItem folderItem = null;
            try
            {
                // See if the folder exists
                folderItem = await ApplicationData.Current.LocalFolder.TryGetItemAsync("Users\\" + PersonName.Text);
            }
            catch (Exception)
            {
                // We don't get an exception if the item doesn't exist. We will if we were passed an illegal
                // path in which case we can't have a user with that name. Or there could be some other
                // issue with that directory name. Regardless you can't use that name.
                this.IsPrimaryButtonEnabled = false;
                textBlock.Text = "Sorry, can't use that name.";
                return;
            }

            // If it doesn't exist, add the user
            if (folderItem == null)
            {
                this.IsPrimaryButtonEnabled = true;
                textBlock.Text = "";
            }
            // If it does, then this user already exists
            else
            {
                this.IsPrimaryButtonEnabled = false;
                textBlock.Text = "This user name already exists.";
            }
        }