How to Bind and Display a ComboBox in a DataGridView Cell using C# and VB.NET

Last updated: 04th July 2025

The DataGridView control in .NET Windows Forms is a powerful tool for displaying and managing data in a structured tabular format. Beyond simple data presentation, it enables seamless data manipulation through database binding, making it a versatile component for dynamic applications. With features that emulate Excel-like behavior, developers can build intuitive and interactive data grids. In this tutorial, we’ll demonstrate how to bind a ComboBox to a DataGridView cell dynamically using C# and VB.NET, allowing users to select predefined values directly within the grid.

Update: See code for C#. I have also explained how to set the name property of each column in the DataGridView and its proper usage.

The ComboBox control automatically appears within a specific DataGridView cell when that cell gains focus. This interactive behavior enables users to effortlessly select a value from a predefined list, enhancing data entry and improving the user experience.

Setting Up Your Windows Forms Project

Start Microsoft Visual Studio and select a "New Project" from the File menu (Left Top Menu).

From the New Project templates, select Windows Forms Application and click OK.

01) A new project appears with a "Blank Form". Click the "Toolbox" button (or press Ctrl+Alt+X keys) to open Toolbox window. Under All Windows Forms, find DataGridView control and "double click" it to add the control in the form.

add datagridview control in windows form

02) Select the DataGridView control and "right click" the mouse to choose Properties. In the Properties window, find the Columns property (under "Misc") and open it. Add few columns like "Employee Name", "Mobile No." etc to the Grid. (See the below Image 👇).

DataGridView Design Mode

To add the columns, simply click the Add button, which will open the "Add Column" window. You will have to add values to the first and last fields, "Name" and "Header Text".

Remember, the "Present Address" column is important for this example to work properly. Therefore, in the "Header Text" field add the text Present Address and in the Name field add "PresentAddress" (without any space).

03) Next, drag and drop a "ComboBox" control onto the DataGridView interface. This ComboBox will display a list of qualifications for the user to select from. To populate the list, right-click on the ComboBox, navigate to Properties, and locate the Items property. There, you can manually add predefined qualification values, such as "Graduate", "Postgraduate", or "Diploma", depending on your application requirements.

bind combo box control to datagridview control

Set the Visible property of the ComboBox control to False during form initialization. This ensures the ComboBox remains hidden when the form loads, preserving a clean interface. It will dynamically appear only when focus is set to a cell within the "Qualification" column of the DataGridView. Until then, the control stays invisible and non-interactive.

Note: The "ComboBox" control should be placed on the "DataGridView" control.

Now, let’s write the code.

Code Behind (C#)

Copy and paste the below code in the code window of your application and run the application.

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace WindowsFormsApplication1
{
    public partial class frmDataGridView_Demo : Form
    {
        DataTable dtTable = new DataTable("Employee");      // CREATE A DATATABLE.

        public frmDataGridView_Demo()
        {
            InitializeComponent();
            addRows();  // ADD FEW BLANK ROWS TO START WITH.
        }

        private void addRows()
        {
            DataRow row = null;
            row = dtTable.NewRow();

            int iCntCol = 0;

            for (iCntCol = 1; iCntCol <= 10; iCntCol++)
            {
                row = dtTable.NewRow();     // ADD BLANK ROWS TO THE DATATABLE.
                dtTable.Rows.Add(row);
            }

            // ADD DATATABLE TO GRID. (WITH THE BLANK ROWS)
            dataGridView1.DataSource = dtTable;

            // ADD SOME COLOR TO THE GRID.
            dataGridView1.GridColor = Color.FromArgb(211, 222, 229);
            dataGridView1.BackgroundColor = Color.Wheat;

            dataGridView1.RowsDefaultCellStyle.BackColor = Color.AliceBlue;
            dataGridView1.RowsDefaultCellStyle.SelectionBackColor = Color.CornflowerBlue;
            dataGridView1.RowsDefaultCellStyle.SelectionForeColor = Color.White;
        }

        // CONTROL THE KEY STROKES.
        protected override bool ProcessCmdKey(ref System.Windows.Forms.Message msg, 
            System.Windows.Forms.Keys keyData)
        {
            if (keyData == Keys.Enter)
            {
                // ON ENTER KEY, GO TO THE NEXT CELL. 
                // WHEN THE CURSOR REACHES THE LAST COLUMN, CARRY IT ON TO THE NEXT ROW.

                if (ActiveControl.Name == "DataGridView1")
                {
                    // CHECK IF ITS THE LAST COLUMN
                    if (dataGridView1.CurrentCell.ColumnIndex == dataGridView1.ColumnCount - 1)
                    {
                        // GO TO THE FIRST COLUMN, NEXT ROW.
                        dataGridView1.CurrentCell = 
                            dataGridView1.Rows[dataGridView1.CurrentCell.RowIndex + 1]
                                .Cells[0];
                    }
                    else
                    {
                        // NEXT COLUMN.
                        dataGridView1.CurrentCell = 
                            dataGridView1.Rows[dataGridView1.CurrentRow.Index]
                            .Cells[dataGridView1.CurrentCell.ColumnIndex + 1];
                    }

                    return true;
                }
                else if (ActiveControl is DataGridViewTextBoxEditingControl)
                {
                    // SHOW THE COMBOBOX WHEN FOCUS IS ON A CELL 
                        CORRESPONDING TO THE "QUALIFICATION" COLUMN.
                    if (dataGridView1.Columns
                        [dataGridView1.CurrentCell.ColumnIndex].Name == "PresentAddress")
                    {
                        dataGridView1.CurrentCell = 
                            dataGridView1.Rows[dataGridView1.CurrentRow.Index]
                                .Cells[dataGridView1.CurrentCell.ColumnIndex + 1];

                        // SHOW COMBOBOX.
                        Show_Combobox(dataGridView1.CurrentRow.Index, 
                            dataGridView1.CurrentCell.ColumnIndex); 

                        SendKeys.Send("{F4}");      // DROP DOWN THE LIST.
                        return true;
                    }
                    else
                    {
                        // CHECK IF ITS THE LAST COLUMN.
                        if (dataGridView1.CurrentCell.ColumnIndex == 
                            dataGridView1.ColumnCount - 1)
                        {
                            // GO TO THE FIRST COLUMN, NEXT ROW.
                            dataGridView1.CurrentCell = 
                                dataGridView1.Rows[dataGridView1.CurrentCell.RowIndex + 1]
                                    .Cells[0];
                        }
                        else
                        {
                            // NEXT COLUMN.
                            dataGridView1.CurrentCell = 
                                dataGridView1.Rows[dataGridView1.CurrentRow.Index]
                                    .Cells[dataGridView1.CurrentCell.ColumnIndex + 1];
                        }
                        return true;
                    }
                }
                else if (ActiveControl.Name == "ComboBox1")
                {
                    // HIDE THE COMBOBOX AND ASSIGN COMBO'S VALUE TO THE CELL.
                    comboBox1.Visible = false;

                    dataGridView1.Focus();

                    // ONCE THE COMBO IS SET AS INVISIBLE, SET FOCUS BACK TO THE GRID. 
                        (IMPORTANT)
                    dataGridView1[dataGridView1.CurrentCell.ColumnIndex, 
                        dataGridView1.CurrentRow.Index].Value = comboBox1.Text;

                    dataGridView1.CurrentCell = 
                        dataGridView1.Rows[dataGridView1.CurrentRow.Index]
                            .Cells[dataGridView1.CurrentCell.ColumnIndex + 1];
                }
                else
                {
                    SendKeys.Send("{TAB}");
                }
                return true;
            }
            else if (keyData == Keys.Escape)            // PRESS ESCAPE TO HIDE THE COMBOBOX.
            {
                if (ActiveControl.Name == "ComboBox1")
                {
                    comboBox1.Text = "";
                    comboBox1.Visible = false;

                    dataGridView1.CurrentCell = 
                        dataGridView1.Rows[dataGridView1.CurrentCell.RowIndex]
                            .Cells[dataGridView1.CurrentCell.ColumnIndex];

                    dataGridView1.Focus();
                }
                return true;
            }
            else
            {
                return base.ProcessCmdKey(ref msg, keyData);
            }
        }

        private void Show_Combobox(int iRowIndex, int iColumnIndex)
        {
            // DESCRIPTION: SHOW THE COMBO BOX IN THE SELECTED CELL OF THE GRID.
            // PARAMETERS: iRowIndex - THE ROW ID OF THE GRID.
            //             iColumnIndex - THE COLUMN ID OF THE GRID.

            int x = 0;
            int y = 0;
            int Width = 0;
            int height = 0;

            // GET THE ACTIVE CELL'S DIMENTIONS TO BIND THE COMBOBOX WITH IT.
            Rectangle rect = default(Rectangle);
            rect = dataGridView1.GetCellDisplayRectangle(iColumnIndex, iRowIndex, false);
            x = rect.X + dataGridView1.Left;
            y = rect.Y + dataGridView1.Top;

            Width = rect.Width;
            height = rect.Height;

            comboBox1.SetBounds(x, y, Width, height);
            comboBox1.Visible = true;
            comboBox1.Focus();
        }
    }
}

When the focus moves to the fourth cell in the DataGridView row, the ComboBox automatically becomes visible, presenting a list of predefined qualification options for the user to choose from. 👇

ComboBox in DataGridView

Code Behind (VB.NET)

Option Explicit On

Public Class frmDataGridView_Demo
    Dim dtTable As New DataTable("Employee")    ' CREATE A DATATABLE.

    Private Sub frmDataGridView_Demo_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
        AddRows()                ' ADD FEW BLANK ROWS TO START WITH.
    End Sub

    Private Sub AddRows()
        Dim row As DataRow
        row = dtTable.NewRow

        For iCntCol = 1 To 10
            row = dtTable.NewRow        ' ADD BLANK ROWS TO THE DATATABLE.
            dtTable.Rows.Add(row)
        Next

        With DataGridView1
            .DataSource = dtTable       ' ADD DATATABLE TO GRID. (WITH THE BLANK ROWS)

            ' JUST FOR THE LOOKS.
            .GridColor = Color.FromArgb(211, 222, 229)
            .BackgroundColor = Color.Wheat

            .RowsDefaultCellStyle.BackColor = Color.AliceBlue
            .RowsDefaultCellStyle.SelectionBackColor = Color.CornflowerBlue
            .RowsDefaultCellStyle.SelectionForeColor = Color.White
        End With
    End Sub

    ' CONTROL THE KEY STROKES.
    Protected Overrides Function ProcessCmdKey(ByRef msg As System.Windows.Forms.Message, _
            ByVal keyData As System.Windows.Forms.Keys) As Boolean

        If keyData = Keys.Enter Then
            ' ON ENTER KEY, GO TO THE NEXT CELL. 
                ' WHEN THE CURSOR REACHES THE LAST COLUMN, CARRY IT ON TO THE NEXT ROW.

            If ActiveControl.Name = "DataGridView1" Then
                With DataGridView1
                    If .CurrentCell.ColumnIndex = .ColumnCount - 1 Then             ' CHECK IF ITS THE LAST COLUMN
                        .CurrentCell = .Rows(.CurrentCell.RowIndex + 1).Cells(0)    ' GO TO THE FIRST COLUMN, NEXT ROW.
                    Else
                        .CurrentCell = .Rows(.CurrentRow.Index).Cells(.CurrentCell.ColumnIndex + 1)     ' NEXT COLUMN.
                    End If
                End With

            ElseIf TypeOf ActiveControl Is DataGridViewTextBoxEditingControl Then

                ' SHOW THE COMBOBOX WHEN FOCUS IS ON A CELL CORRESPONDING TO THE "QUALIFICATION" COLUMN.
                With DataGridView1
                    If .Columns(.CurrentCell.ColumnIndex).Name = "PresentAddress" Then
                        .CurrentCell = .Rows(.CurrentRow.Index).Cells(.CurrentCell.ColumnIndex + 1)

                        ' SHOW COMBOBOX.
                        Show_Combobox(.CurrentRow.Index, .CurrentCell.ColumnIndex)
                        SendKeys.Send("{F4}")               ' DROP DOWN THE LIST.
                    Else
                        If .CurrentCell.ColumnIndex = .ColumnCount - 1 Then             ' CHECK IF ITS THE LAST COLUMN
                            .CurrentCell = .Rows(.CurrentCell.RowIndex + 1).Cells(0)    ' GO TO THE FIRST COLUMN, NEXT ROW.
                        Else
                            .CurrentCell = .Rows(.CurrentRow.Index).Cells(.CurrentCell.ColumnIndex + 1)     ' NEXT COLUMN.
                        End If
                    End If
                End With

            ElseIf ActiveControl.Name = "ComboBox1" Then
                ' HIDE THE COMBOBOX AND ASSIGN COMBO'S VALUE TO THE CELL.
                ComboBox1.Visible = False

                With DataGridView1
                    .Focus()            ' ONCE THE COMBO IS SET AS INVISIBLE, SET FOCUS BACK TO THE GRID. (IMPORTANT)
                    .Item(.CurrentCell.ColumnIndex, .CurrentRow.Index).Value = Trim(ComboBox1.Text)
                    .CurrentCell = .Rows(.CurrentRow.Index).Cells(.CurrentCell.ColumnIndex + 1)
                End With
            Else
                SendKeys.Send("{TAB}")
            End If

            Return True
        ElseIf keyData = Keys.Escape Then       ' PRESS ESCAPE TO HIDE THE COMBOBOX.
            If ActiveControl.Name = "ComboBox1" Then
                ComboBox1.Text = "" : ComboBox1.Visible = False

                With DataGridView1
                    .CurrentCell = .Rows(.CurrentCell.RowIndex).Cells(.CurrentCell.ColumnIndex)
                    .Focus()
                    Return True
                End With
            End If
        Else
            Return MyBase.ProcessCmdKey(msg, keyData)
        End If
    End Function

    Private Sub Show_Combobox(ByVal iRowIndex As Integer, ByVal iColumnIndex As Integer)
        ' DESCRIPTION: SHOW THE COMBO BOX IN THE SELECTED CELL OF THE GRID.
        ' PARAMETERS: iRowIndex - THE ROW ID OF THE GRID.
        '             iColumnIndex - THE COLUMN ID OF THE GRID.

        Dim x As Integer = 0
        Dim y As Integer = 0
        Dim Width As Integer = 0
        Dim height As Integer = 0

        ' GET THE ACTIVE CELL'S DIMENTIONS TO BIND THE COMBOBOX WITH IT.
        Dim rect As Rectangle
        rect = DataGridView1.GetCellDisplayRectangle(iColumnIndex, iRowIndex, False)
        x = rect.X + DataGridView1.Left
        y = rect.Y + DataGridView1.Top

        Width = rect.Width
        height = rect.Height

        With ComboBox1
            .SetBounds(x, y, Width, height)
            .Visible = True
            .Focus()
        End With
    End Sub
End Class

Conclusion

Integrating a ComboBox into a DataGridView control is a practical way to enhance data entry, validation, and user experience within .NET Windows Forms applications. By dynamically binding the ComboBox to specific cells—such as those under the "Qualification" column—you create a more interactive and intuitive interface for end users. Whether you're working with C# or VB.NET, the techniques demonstrated in this tutorial offer a reusable pattern for enriching your forms with dropdown selection functionality. Try it out in your next project to see how seamlessly it fits into real-world applications.

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