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How to: Access Objects Bound to Windows Forms DataGridView Rows

Sometimes it is useful to display a table of information stored in a collection of business objects. When you bind a DataGridView control to such a collection, each public property is displayed in its own column unless the property has been marked non-browsable with a BrowsableAttribute. For example, a collection of Customer objects would have columns such as Name and Address.

If these objects contain additional information and code that you want to access, you can reach it through row objects. In the following code example, users can select multiple rows and click a button to send an invoice to each of the corresponding customers.

To access row-bound objects

  • Use the DataGridViewRow.DataBoundItem property.

    Private Sub InvoiceButton_Click(ByVal sender As System.Object, _
        ByVal e As System.EventArgs) Handles InvoiceButton.Click
    
        For Each row As DataGridViewRow In Me.DataGridView1.SelectedRows
    
            Dim cust As Customer = TryCast(row.DataBoundItem, Customer)
            If cust IsNot Nothing Then
                cust.SendInvoice()
            End If 
    
        Next 
    
    End Sub
    
    void invoiceButton_Click(object sender, EventArgs e)
    {
        foreach (DataGridViewRow row in this.dataGridView1.SelectedRows)
        {
            Customer cust = row.DataBoundItem as Customer;
            if (cust != null)
            {
                cust.SendInvoice();
            }
        }
    }
    

Example

The complete code example includes a simple Customer implementation and binds the DataGridView to an ArrayList containing a few Customer objects. The Click event handler of the System.Windows.Forms.Button must access the Customer objects through the rows, because the customer collection is not accessible outside the Form.Load event handler.

Imports System
Imports System.Windows.Forms

Public Class DataGridViewObjectBinding
    Inherits Form

    ' These declarations and the Main() and New() methods  
    ' below can be replaced with designer-generated code.  
    Private WithEvents InvoiceButton As New Button()
    Private WithEvents DataGridView1 As New DataGridView()

    ' Entry point code. 
    <STAThreadAttribute()> _
    Public Shared Sub Main()

        Application.Run(New DataGridViewObjectBinding())

    End Sub 

    ' Sets up the form.  
    Public Sub New()

        Me.DataGridView1.Dock = DockStyle.Fill
        Me.Controls.Add(Me.DataGridView1)

        Me.InvoiceButton.Text = "invoice the selected customers" 
        Me.InvoiceButton.Dock = DockStyle.Top
        Me.Controls.Add(Me.InvoiceButton)
        Me.Text = "DataGridView collection-binding demo" 

    End Sub 

    Private Sub Form1_Load(ByVal sender As System.Object, _
        ByVal e As System.EventArgs) Handles MyBase.Load

        ' Set up a collection of objects for binding. 
        Dim customers As New System.Collections.ArrayList()
        customers.Add(New Customer("Harry"))
        customers.Add(New Customer("Sally"))
        customers.Add(New Customer("Roy"))
        customers.Add(New Customer("Pris"))

        ' Initialize and bind the DataGridView. 
        Me.DataGridView1.SelectionMode = _
            DataGridViewSelectionMode.FullRowSelect
        Me.DataGridView1.AutoGenerateColumns = True 
        Me.DataGridView1.DataSource = customers

    End Sub 

    ' Calls the SendInvoice() method for the Customer  
    ' object bound to each selected row. 
    Private Sub InvoiceButton_Click(ByVal sender As System.Object, _
        ByVal e As System.EventArgs) Handles InvoiceButton.Click

        For Each row As DataGridViewRow In Me.DataGridView1.SelectedRows

            Dim cust As Customer = TryCast(row.DataBoundItem, Customer)
            If cust IsNot Nothing Then
                cust.SendInvoice()
            End If 

        Next 

    End Sub 

End Class 

Public Class Customer

    Private nameValue As String 

    Public Sub New(ByVal name As String)
        nameValue = name
    End Sub 

    Public Property Name() As String 
        Get 
            Return nameValue
        End Get 
        Set(ByVal value As String)
            nameValue = value
        End Set 
    End Property 

    Public Sub SendInvoice()
        MsgBox(nameValue & " has been billed.")
    End Sub 

End Class
using System;
using System.Windows.Forms;

public class DataGridViewObjectBinding : Form
{
    // These declarations and the Main() and New() methods  
    // below can be replaced with designer-generated code.  
    private Button invoiceButton = new Button();
    private DataGridView dataGridView1 = new DataGridView();

    // Entry point code. 
    [STAThreadAttribute()]
    public static void Main()
    {
        Application.Run(new DataGridViewObjectBinding());
    }

    // Sets up the form. 
    public DataGridViewObjectBinding()
    {
        this.dataGridView1.Dock = DockStyle.Fill;
        this.Controls.Add(this.dataGridView1);

        this.invoiceButton.Text = "invoice the selected customers";
        this.invoiceButton.Dock = DockStyle.Top;
        this.invoiceButton.Click += new EventHandler(invoiceButton_Click);
        this.Controls.Add(this.invoiceButton);

        this.Load += new EventHandler(DataGridViewObjectBinding_Load);
        this.Text = "DataGridView collection-binding demo";
    }

    void  DataGridViewObjectBinding_Load(object sender, EventArgs e)
    {
        // Set up a collection of objects for binding.
        System.Collections.ArrayList customers = new System.Collections.ArrayList();
        customers.Add(new Customer("Harry"));
        customers.Add(new Customer("Sally"));
        customers.Add(new Customer("Roy"));
        customers.Add(new Customer("Pris"));

        // Initialize and bind the DataGridView. 
        this.dataGridView1.SelectionMode = 
            DataGridViewSelectionMode.FullRowSelect;
        this.dataGridView1.AutoGenerateColumns = true;
        this.dataGridView1.DataSource = customers;
    }

    // Calls the SendInvoice() method for the Customer  
    // object bound to each selected row. 
    void invoiceButton_Click(object sender, EventArgs e)
    {
        foreach (DataGridViewRow row in this.dataGridView1.SelectedRows)
        {
            Customer cust = row.DataBoundItem as Customer;
            if (cust != null)
            {
                cust.SendInvoice();
            }
        }
    }
}

public class Customer
{
    private String nameValue;

    public Customer(String name)
    {
        nameValue = name;
    }

    public String Name
    {
        get
        {
            return nameValue;
        }
        set 
        {
            nameValue = value;
        }
    }

    public void SendInvoice()
    {
        MessageBox.Show(nameValue + " has been billed.");
    }
}

Compiling the Code

This example requires:

  • References to the System and System.Windows.Forms assemblies.

For information about building this example from the command line for Visual Basic or Visual C#, see Building from the Command Line (Visual Basic) or Command-line Building With csc.exe. You can also build this example in Visual Studio by pasting the code into a new project. How to: Compile and Run a Complete Windows Forms Code Example Using Visual Studio
How to: Compile and Run a Complete Windows Forms Code Example Using Visual Studio
How to: Compile and Run a Complete Windows Forms Code Example Using Visual Studio
How to: Compile and Run a Complete Windows Forms Code Example Using Visual Studio

See Also

Tasks

How to: Bind Objects to Windows Forms DataGridView Controls

Reference

DataGridView

DataGridViewRow

DataGridViewRow.DataBoundItem

Other Resources

Displaying Data in the Windows Forms DataGridView Control