Customer Management

Overview

The Customer Management module provides complete CRUD functionality for managing customer information. The system stores detailed customer profiles including personal information, contact details, and addresses.

Customer Model

The Customer model (Models/Customer.cs:3-13) defines a comprehensive customer profile:

public class Customer
{
    public int Id { get; set; }
    public string Document { get; set; }
    public string FirstName { get; set; }
    public string LastName { get; set; }
    public string Address { get; set; }
    public DateTime Birthday { get; set; }
    public string PhoneNumber { get; set; }
    public string Email { get; set; }
}

Properties

Property	Type	Description	Example
`Id`	int	Unique identifier	1
`Document`	string	Government-issued ID number	”12345678”
`FirstName`	string	Customer’s first name	”John”
`LastName`	string	Customer’s last name	”Smith”
`Address`	string	Physical address	”123 Main St”
`Birthday`	DateTime	Date of birth	1990-05-15
`PhoneNumber`	string	Contact phone number	”+1-555-0123”
`Email`	string	Email address	”[email protected]”

The Customer model captures all essential information needed for customer relationship management, loyalty programs, and communication.

CRUD Operations

List Customers
Create Customer
Edit Customer
Delete Customer

Viewing All Customers

The Index page (Pages/Customers/Index.cshtml.cs:22-28) displays all customer records:

public IList<Customer> Customers { get; set; } = default!;

public async Task OnGetAsync()
{
    if (_context.Customers != null)
    {
        Customers = await _context.Customers.ToListAsync();
    }
}

The page loads all customers asynchronously and exposes them through the Customers property for display in the view.

Adding New Customers

New customers are added through the Create page following the standard pattern:

[BindProperty]
public Customer Customer { get; set; } = default!;

public async Task<IActionResult> OnPostAsync()
{
    if (!ModelState.IsValid || _context.Customers == null || Customer == null)
    {
        return Page();
    }

    _context.Customers.Add(Customer);
    await _context.SaveChangesAsync();

    return RedirectToPage("./Index");
}

Input Validation

ModelState checks ensure all required fields are provided

Add to Context

Customer is added to Entity Framework context

Persist Data

SaveChangesAsync commits the new customer to the database

Navigate

User is redirected to the customer list

Updating Customer Information

The Edit page handles customer updates:

[BindProperty]
public Customer Customer { get; set; } = default!;

public async Task<IActionResult> OnGetAsync(int? id)
{
    if (id == null || _context.Customers == null)
    {
        return NotFound();
    }

    var customer = await _context.Customers.FirstOrDefaultAsync(m => m.Id == id);

    if (customer == null)
    {
        return NotFound();
    }
    Customer = customer;
    return Page();
}

public async Task<IActionResult> OnPostAsync()
{
    if (!ModelState.IsValid)
    {
        return Page();
    }

    _context.Attach(Customer).State = EntityState.Modified;

    try
    {
        await _context.SaveChangesAsync();
    }
    catch (DbUpdateConcurrencyException)
    {
        if (!CustomerExists(Customer.Id))
        {
            return NotFound();
        }
        else
        {
            throw;
        }
    }

    return RedirectToPage("./Index");
}

Removing Customer Records

The Delete page provides confirmation before removing customers:

[BindProperty]
public Customer Customer { get; set; } = default!;

public async Task<IActionResult> OnGetAsync(int? id)
{
    if (id == null || _context.Customers == null)
    {
        return NotFound();
    }

    var customer = await _context.Customers.FirstOrDefaultAsync(m => m.Id == id);

    if (customer == null)
    {
        return NotFound();
    }
    else
    {
        Customer = customer;
    }
    return Page();
}

public async Task<IActionResult> OnPostAsync(int? id)
{
    if (id == null || _context.Customers == null)
    {
        return NotFound();
    }

    var customer = await _context.Customers.FindAsync(id);

    if (customer != null)
    {
        Customer = customer;
        _context.Customers.Remove(customer);
        await _context.SaveChangesAsync();
    }

    return RedirectToPage("./Index");
}

Customer Information Fields

Personal Information

Document

Government-issued identification number for unique customer identification

Name

Full name split into FirstName and LastName for proper addressing

Birthday

Date of birth for age verification and birthday promotions

Address

Physical address for delivery and communication purposes

Contact Information

Email

Primary email address for digital communication

Phone Number

Contact phone number for urgent communication

Authorization

All customer management operations require authentication:

[Authorize]
public class IndexModel : PageModel
{
    // Implementation
}

Customer data contains personally identifiable information (PII). Only authenticated users can access customer management features.

Database Context

Customers are managed through the SupermarketContext (Data/SupermarketContext.cs:15):

public DbSet<Customer> Customers { get; set; }

Page Structure

The customer management module consists of four Razor Pages:

Page	Route	Purpose
Index	`/Pages/Customers/Index.cshtml`	Display all customers
Create	`/Pages/Customers/Create.cshtml`	Add new customer
Edit	`/Pages/Customers/Edit.cshtml`	Update customer details
Delete	`/Pages/Customers/Delete.cshtml`	Remove customer record

Validation Best Practices

Consider adding validation attributes to ensure data quality:

public class Customer
{
    public int Id { get; set; }
    
    [Required]
    [StringLength(20)]
    public string Document { get; set; }
    
    [Required]
    [StringLength(50)]
    public string FirstName { get; set; }
    
    [Required]
    [StringLength(50)]
    public string LastName { get; set; }
    
    [Required]
    [StringLength(200)]
    public string Address { get; set; }
    
    [Required]
    [DataType(DataType.Date)]
    public DateTime Birthday { get; set; }
    
    [Required]
    [Phone]
    [StringLength(20)]
    public string PhoneNumber { get; set; }
    
    [Required]
    [EmailAddress]
    [StringLength(100)]
    public string Email { get; set; }
}

Adding data annotations improves input validation and provides better user feedback when invalid data is entered.

Common Operations

Search by Email

var customer = await _context.Customers
    .FirstOrDefaultAsync(c => c.Email == email);

Search by Document

var customer = await _context.Customers
    .FirstOrDefaultAsync(c => c.Document == documentNumber);

Find Customers by Name

var customers = await _context.Customers
    .Where(c => c.FirstName.Contains(searchTerm) || c.LastName.Contains(searchTerm))
    .ToListAsync();

Birthday List for Current Month

var currentMonth = DateTime.Now.Month;
var birthdayCustomers = await _context.Customers
    .Where(c => c.Birthday.Month == currentMonth)
    .OrderBy(c => c.Birthday.Day)
    .ToListAsync();

Privacy and Security

PII Protection

Customer data contains sensitive PII requiring proper protection

Access Control

Implement role-based access for viewing customer information

Audit Logging

Track who accesses and modifies customer records

Data Encryption

Consider encrypting sensitive fields at rest and in transit

Advanced Features

Customer Segmentation

Group customers by demographics, purchase history, or behavior for targeted marketing campaigns.

Loyalty Programs

Use customer data to implement point-based loyalty programs and track reward balances.

Purchase History

Link customers to their transaction history for personalized recommendations and analytics.

Communication Preferences

Add fields to track customer preferences for email, SMS, and promotional communications.

For international deployments, consider implementing:

Right to Access: Allow customers to request their data
Right to Rectification: Easy data correction mechanisms
Right to Erasure: “Delete my account” functionality
Data Portability: Export customer data in standard formats
Consent Management: Track consent for data processing and marketing

Deleting customer records may impact referential integrity if linked to orders or transactions. Consider soft deletes or data archival strategies.

Get Started

Core Features

Data Models

Development

Overview

Customer Model

Properties

CRUD Operations

Viewing All Customers

Adding New Customers

Updating Customer Information

Removing Customer Records

Customer Information Fields

Personal Information

Document

Name

Birthday

Address

Contact Information

Email

Phone Number

Authorization

Database Context

Page Structure

Validation Best Practices

Common Operations

Search by Email

Search by Document

Find Customers by Name

Birthday List for Current Month

Privacy and Security

PII Protection

Access Control

Audit Logging

Data Encryption

Advanced Features

Build docs developers (and LLMs) love

Get Started

Core Features

Data Models

Development

​Overview

​Customer Model

​Properties

​CRUD Operations

​Viewing All Customers

​Adding New Customers

​Updating Customer Information

​Removing Customer Records

​Customer Information Fields

​Personal Information

Document

Name

Birthday

Address

​Contact Information

Email

Phone Number

​Authorization

​Database Context

​Page Structure

​Validation Best Practices

​Common Operations

​Search by Email

​Search by Document

​Find Customers by Name

​Birthday List for Current Month

​Privacy and Security

PII Protection

Access Control

Audit Logging

Data Encryption

​Advanced Features

​GDPR Compliance

Build docs developers (and LLMs) love

Overview

Customer Model

Properties

CRUD Operations

Viewing All Customers

Adding New Customers

Updating Customer Information

Removing Customer Records

Customer Information Fields

Personal Information

Contact Information

Authorization

Database Context

Page Structure

Validation Best Practices

Common Operations

Search by Email

Search by Document

Find Customers by Name

Birthday List for Current Month

Privacy and Security

Advanced Features

GDPR Compliance