UWP Development, Data Validation - Single Item Validation

Author: [Author Name]

October 10, 2023

Introduction

Data validation in UWP (Universal Windows Platform) development is a crucial aspect that enhances the application’s reliability and usability. This article will detail the concept of single-item validation and how to implement it. Single-item validation is the process of verifying the value of each field input by the user to ensure its validity.

Preventing incorrect data entry reduces errors in the application and helps users have a smooth experience. Particularly, in UWP applications, data validation is an important part related to security. This article will implement single-item validation in a UWP application using C# and XAML.

The Importance of Single-Item Validation

Single-item validation is essential for restricting user input and maintaining the quality of data in the application. For example, when collecting important information such as a user’s email address or phone number, it is crucial to validate whether the format is correct. This allows for:

Prevention of storing incorrect data.
Providing immediate feedback to users.
Enhancing the reliability of the application.

Implementing Data Validation

Now, let’s implement single-item validation in a UWP application. We will explain it based on a simple example. In this example, we will create a simple UI that includes a TextBox for users to input their email address and a button to validate the email address when clicked.

1. Building the XAML UI

Here is the code for the UI constructed in XAML.

<Page
    x:Class="UWPValidationExample.MainPage"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:local="using:UWPValidationExample"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    mc:Ignorable="d">

    <Grid>
        <StackPanel Margin="20">
            <TextBox x:Name="EmailTextBox" PlaceholderText="Enter email address" Width="300" />
            <Button Content="Validate" Click="ValidateButton_Click" Width="100" Margin="0,10,0,0" />
            <TextBlock x:Name="ResultTextBlock" Margin="0,10,0,0" FontWeight="Bold" />
        </StackPanel>
    </Grid>
</Page>

The above code sets up a basic layout that includes a TextBox for entering an email address, a validation button, and a TextBlock to display the result.

2. Implementing Validation Logic in C# Code

Next, we will write the C# code to handle the button click event. This code validates the entered email address and displays the result in the TextBlock.

using System;
using System.Text.RegularExpressions;
using Windows.UI.Xaml;
using Windows.UI.Xaml.Controls;

namespace UWPValidationExample
{
    public sealed partial class MainPage : Page
    {
        public MainPage()
        {
            this.InitializeComponent();
        }

        private void ValidateButton_Click(object sender, RoutedEventArgs e)
        {
            string email = EmailTextBox.Text;
            if (IsValidEmail(email))
            {
                ResultTextBlock.Text = "Valid email address.";
                ResultTextBlock.Foreground = new SolidColorBrush(Windows.UI.Colors.Green);
            }
            else
            {
                ResultTextBlock.Text = "Invalid email address.";
                ResultTextBlock.Foreground = new SolidColorBrush(Windows.UI.Colors.Red);
            }
        }

        private bool IsValidEmail(string email)
        {
            var emailRegex = new Regex(@"^[^@\s]+@[^@\s]+\.[^@\s]+$");
            return emailRegex.IsMatch(email);
        }
    }
}

In the above code, the IsValidEmail method uses a regular expression to validate the format of the entered email address. This method is called when the button is clicked to check if the email is valid and displays the result in the TextBlock.

Testing and Validation

After running the app, you can input an email address and click the ‘Validate’ button to test the email address’s validity. If a valid email address is entered, it will display “Valid email address.” in green text, and if an incorrect format is entered, it will display “Invalid email address.” in red text. This provides immediate feedback to the user, helping to prevent incorrect input.

Conclusion

Single-item validation plays a crucial role in safely handling data input in UWP applications. In this article, we explored the necessity of single-item validation and how to implement it through a simple example of validating an email address.

These validation logics can be applied to multiple items to make the application’s data more robust. Additionally, more complex validation logics can be implemented for various input items, further enhancing the user’s experience.

Based on the example above, consider adding data validation features to your UWP applications to create a safer and more reliable application.

UWP Development, Data Validation – Single Item Validation