Introduction

Data binding connects UI controls to data sources, allowing automatic synchronization of values. This tutorial guides you through basic and advanced scenarios using Windows Forms.

What is Data Binding?

WinForms supports several binding types:

• Simple binding – bind a single property.
• Complex binding – bind to a list or collection.
• Two‑way binding – changes propagate both ways.

Simple Example

Bind a TextBox to a Customer.Name property.

Copypublic partial class Form1 : Form
{
    private Customer _customer = new Customer { Name = "Alice" };

    public Form1()
    {
        InitializeComponent();
        textBoxName.DataBindings.Add("Text", _customer, "Name", true, DataSourceUpdateMode.OnPropertyChanged);
    }
}

public class Customer : INotifyPropertyChanged
{
    private string _name;
    public string Name
    {
        get => _name;
        set
        {
            if (_name != value) { _name = value; OnPropertyChanged(nameof(Name)); }
        }
    }

    public event PropertyChangedEventHandler PropertyChanged;
    protected void OnPropertyChanged(string prop) => PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(prop));
}

Binding to a List

Display a collection of objects in a DataGridView using a BindingList.

Copypublic partial class Form2 : Form
{
    private BindingList _products = new BindingList
    {
        new Product { Id = 1, Name = "Laptop", Price = 999.99m },
        new Product { Id = 2, Name = "Smartphone", Price = 599.49m },
    };

    public Form2()
    {
        InitializeComponent();
        dataGridViewProducts.AutoGenerateColumns = true;
        dataGridViewProducts.DataSource = _products;
    }
}

public class Product
{
    public int Id { get; set; }
    public string Name { get; set; }
    public decimal Price { get; set; }
}

Two‑Way Binding

Synchronize a ComboBox selection with a property on the current object.

Copypublic partial class Form3 : Form
{
    private BindingSource _bs = new BindingSource();

    public Form3()
    {
        InitializeComponent();
        var colors = new List { "Red", "Green", "Blue" };
        _bs.DataSource = new Settings { SelectedColor = "Green" };
        comboBoxColors.DataSource = colors;
        comboBoxColors.DataBindings.Add("SelectedItem", _bs, "SelectedColor", true, DataSourceUpdateMode.OnPropertyChanged);
    }
}

public class Settings : INotifyPropertyChanged
{
    private string _selectedColor;
    public string SelectedColor
    {
        get => _selectedColor;
        set { if (_selectedColor != value){ _selectedColor = value; OnPropertyChanged(nameof(SelectedColor)); } }
    }

    public event PropertyChangedEventHandler PropertyChanged;
    protected void OnPropertyChanged(string name) => PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(name));
}

Summary

Data binding simplifies UI development by reducing boilerplate code. Explore more advanced topics such as custom formatters, currency managers, and binding validation in the Advanced Binding guide.