Credit Card Events

This feature notifies your application of significant changes in the credit card input process via dedicated events, enabling dynamic UI updates and processing based on the card number's state.

Overview

The Credit Card Events feature provides three key events—CardNumberCompleted, CardValidationChanged, and CardTypeChanged—that allow your application to react when:

• The card number entry reaches an expected length,

• The validity of the card number (e.g., as determined by the Luhn algorithm) changes, or

• The detected card type changes based on the entered digits.

By subscribing to these events, developers can trigger UI updates, validations, or further processing (such as enabling a submission button) based on the current state of the card number input.

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Event Details

The table below summarizes the key events associated with credit card input:

Event Name	Description	Usage / Notes
CardNumberCompleted	Fired when the input reaches a known complete length for the detected card type.	Use to trigger further processing once the card entry is complete.
CardValidationChanged	Fired when the validity state of the card number changes (for example, from invalid to valid, or vice versa).	Subscribe to update visual cues or enable/disable UI controls.
CardTypeChanged	Fired when the detected card type changes as the user enters more digits.	Use to update the displayed card logo or other card-type dependent UI elements.

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Code Examples

Example 1: Handling CardNumberCompleted Event

This example demonstrates how to subscribe to the CardNumberCompleted event to process the formatted and unformatted card numbers once the user has completed entering the card number.

// Create an instance of the SiticoneCardNumberBox control
SiticoneCardNumberBox cardNumberBox = new SiticoneCardNumberBox();

// Subscribe to the CardNumberCompleted event
cardNumberBox.CardNumberCompleted += (sender, e) =>
{
    Console.WriteLine("Card entry complete.");
    Console.WriteLine("Formatted Number: " + e.FormattedCardNumber);
    Console.WriteLine("Unformatted Number: " + e.UnformattedCardNumber);
    Console.WriteLine("Detected Card Type: " + e.CardType);
};

// Add the control to the form
this.Controls.Add(cardNumberBox);
cardNumberBox.Location = new Point(20, 20);
cardNumberBox.Size = new Size(350, 50);

Example 2: Responding to CardValidationChanged Event

This example shows how to react when the card number validation status changes.

// Subscribe to the CardValidationChanged event
cardNumberBox.CardValidationChanged += (sender, e) =>
{
    if (e.IsValid)
    {
        Console.WriteLine("The card number is valid.");
        // Enable payment processing or update the UI accordingly.
    }
    else
    {
        Console.WriteLine("The card number is invalid: " + e.ErrorMessage);
        // Disable further processing or display an error message.
    }
};

Example 3: Updating UI on CardTypeChanged Event

This example illustrates how to update the UI when the detected card type changes, such as updating a card logo.

// Subscribe to the CardTypeChanged event
cardNumberBox.CardTypeChanged += (sender, e) =>
{
    Console.WriteLine($"Card type changed from {e.OldCardType} to {e.NewCardType}");
    // Update the card logo image based on e.NewCardType, if applicable.
};

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Key Points

The table below summarizes the key aspects of the Credit Card Events feature:

Topic	Description
Event-driven Updates	Events provide immediate notification when the card number entry reaches completion, changes validity, or updates the detected card type.
UI and Processing Hooks	These events allow your application to update the UI dynamically and trigger processing routines as soon as key input milestones are reached.
Integrated Validation	The events are tied into the control’s built‑in validation and formatting logic, ensuring consistency.

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Best Practices

The table below outlines best practices when using credit card events:

Best Practice	Explanation
Subscribe to all key events	Handle CardNumberCompleted, CardValidationChanged, and CardTypeChanged events to provide complete feedback to the user.
Update the UI immediately after event triggers	For example, update card logos and validation indicators as soon as a card type or validation state changes.
Use the events to enable/disable subsequent processing	Prevent users from proceeding until a complete, valid card number is entered.
Test with various card inputs	Validate event behavior across different card types and edge cases to ensure reliability.

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Common Pitfalls

The table below lists common pitfalls and strategies to avoid them:

Pitfall	How to Avoid It
Ignoring the CardNumberCompleted event	Ensure that you subscribe to this event to catch when the card number entry is complete for processing.
Not updating UI elements in real time	Use the CardValidationChanged and CardTypeChanged events to update the UI as soon as the state changes.
Relying solely on manual checks without event hooks	Leverage these events to automatically manage UI state and validation instead of periodic manual checks.

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Usage Scenarios

The table below describes several scenarios where credit card events are essential:

Scenario	Description
Payment Processing Forms	Automatically trigger card verification and enable payment submission when the card number entry is complete and valid.
Dynamic User Interface Updates	Update the card logo or display error messages dynamically as the user types the card number.
Data Validation Workflows	Use events to initiate back-end calls or validations once a complete and valid card number is detected.

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Real Life Usage Scenarios

Scenario	Example
E-commerce Checkout	When a user enters their credit card number, the CardNumberCompleted event can trigger an automatic format check and update a visual card logo.
Mobile Payment Application	The CardValidationChanged event is used to instantly validate input, showing green if valid or red if invalid, enhancing trust.
Subscription Management System	CardTypeChanged events help to dynamically update UI elements (such as logos or instructions) as different card types are entered.

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Troubleshooting Tips

The table below provides troubleshooting advice for issues related to credit card events:

Issue	Potential Cause	Recommended Action
Events not firing as expected	Event subscriptions might not have been established.	Confirm that event handlers are correctly subscribed to the control’s events.
Inconsistent card type detection	The input may not be correctly formatted or might contain non-digit characters.	Validate the input format and ensure only numeric characters are processed.
Delayed UI updates following event triggers	Heavy processing or blocking operations in the event handler.	Offload processing tasks to background threads or use asynchronous handling if necessary.

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Review

The table below summarizes the review of the Credit Card Events feature:

Aspect	Review Notes
Automation	Automatic event triggering based on card input minimizes manual validation code and reduces development effort.
Dynamic Feedback	Real-time events allow immediate UI updates, significantly improving the end-user experience.
Integration Ease	Built‑in events provide a plug-and-play solution for common credit card processing tasks in payment forms.

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Summary

The Credit Card Events feature of the SiticoneCardNumberBox control streamlines the process of handling credit card input by providing built‑in events for key input milestones. By leveraging CardNumberCompleted, CardValidationChanged, and CardTypeChanged events, developers can easily trigger UI updates, initiate validation logic, and respond to dynamic changes in the input. This event-driven approach ensures that your application remains responsive and provides immediate feedback, improving both usability and efficiency.

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Additional Integration Example

Below is a complete integration example that demonstrates how to subscribe to all credit card events and update the UI accordingly in a WinForms application:

public partial class PaymentProcessingForm : Form
{
    public PaymentProcessingForm()
    {
        InitializeComponent();
        InitializeCardNumberBoxWithEvents();
    }

    private void InitializeCardNumberBoxWithEvents()
    {
        // Create and configure the card number box
        SiticoneCardNumberBox cardNumberBox = new SiticoneCardNumberBox
        {
            Location = new Point(20, 20),
            Size = new Size(350, 50),
            Text = ""
        };

        // Subscribe to CardNumberCompleted event
        cardNumberBox.CardNumberCompleted += (sender, e) =>
        {
            // Process completed card entry (e.g., enable submit button)
            Console.WriteLine("Card entry complete.");
            Console.WriteLine("Formatted: " + e.FormattedCardNumber);
            Console.WriteLine("Unformatted: " + e.UnformattedCardNumber);
        };

        // Subscribe to CardValidationChanged event
        cardNumberBox.CardValidationChanged += (sender, e) =>
        {
            if (e.IsValid)
            {
                Console.WriteLine("Card number is valid.");
                // Optionally, update the UI to reflect valid input (e.g., set border color to green)
            }
            else
            {
                Console.WriteLine("Card number is invalid: " + e.ErrorMessage);
                // Optionally, update the UI to indicate error (e.g., set border color to red)
            }
        };

        // Subscribe to CardTypeChanged event
        cardNumberBox.CardTypeChanged += (sender, e) =>
        {
            Console.WriteLine($"Card type changed from {e.OldCardType} to {e.NewCardType}");
            // Update the UI to display the appropriate card logo based on the new card type
        };

        // Add the control to the form
        this.Controls.Add(cardNumberBox);
    }
}

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By following this documentation, developers can effectively integrate and utilize the Credit Card Events feature of the SiticoneCardNumberBox control. Leveraging these events will enable your application to dynamically respond to user input, perform immediate validations, and provide a smoother and more interactive user experience.