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How to: Manipulate Bands in the Windows Forms DataGridView Control

The following code example shows various ways to manipulate DataGridView rows and columns using properties of the DataGridViewBand class from which the DataGridViewRow and DataGridViewColumn classes derive.

Example

Imports System.Windows.Forms
Imports System.Drawing

Public Class DataGridViewBandDemo
    Inherits Form

#Region "Form setup"
    Public Sub New()
        MyBase.New()
        InitializeComponent()

        AddButton(Button1, "Reset")
        AddButton(Button2, "Change Column 3 Header")
        AddButton(Button3, "Change Meatloaf Recipe")
        AddAdditionalButtons()
    End Sub

    Friend WithEvents dataGridView As DataGridView
    Friend WithEvents Button1 As Button = New Button()
    Friend WithEvents Button2 As Button = New Button()
    Friend WithEvents Button3 As Button = New Button()
    Friend WithEvents Button4 As Button = New Button()
    Friend WithEvents Button5 As Button = New Button()
    Friend WithEvents Button6 As Button = New Button()
    Friend WithEvents Button7 As Button = New Button()
    Friend WithEvents Button8 As Button = New Button()
    Friend WithEvents Button9 As Button = New Button()
    Friend WithEvents Button10 As Button = New Button()
    Friend WithEvents FlowLayoutPanel1 As FlowLayoutPanel _
        = New FlowLayoutPanel()

    Private Sub InitializeComponent()
        FlowLayoutPanel1.Location = New Point(454, 0)
        FlowLayoutPanel1.AutoSize = True
        FlowLayoutPanel1.FlowDirection = FlowDirection.TopDown
        FlowLayoutPanel1.Name = "flowlayoutpanel"
        ClientSize = New System.Drawing.Size(614, 360)
        Controls.Add(FlowLayoutPanel1)
        Text = Me.GetType.Name
        AutoSize = True
    End Sub
#End Region

#Region "setup DataGridView"
    Private thirdColumnHeader As String = "Main Ingredients"
    Private boringMeatloaf As String = "ground beef"
    Private boringMeatloafRanking As String = "*"
    Private boringRecipe As Boolean
    Private shortMode As Boolean

    Private Sub InitializeDataGridView(ByVal ignored As Object, _
    ByVal ignoredToo As EventArgs) Handles Me.Load

        dataGridView = New System.Windows.Forms.DataGridView
        Controls.Add(dataGridView)
        dataGridView.Size = New Size(300, 200)

        ' Create an unbound DataGridView by declaring a
        ' column count.
        dataGridView.ColumnCount = 4
        AdjustDataGridViewSizing()

        ' Set the column header style.
        Dim columnHeaderStyle As New DataGridViewCellStyle
        columnHeaderStyle.BackColor = Color.Aqua
        columnHeaderStyle.Font = _
            New Font("Verdana", 10, FontStyle.Bold)
        dataGridView.ColumnHeadersDefaultCellStyle = _
            columnHeaderStyle

        ' Set the column header names.
        dataGridView.Columns(0).Name = "Recipe"
        dataGridView.Columns(1).Name = "Category"
        dataGridView.Columns(2).Name = thirdColumnHeader
        dataGridView.Columns(3).Name = "Rating"

        ' Populate the rows.
        Dim row1 As String() = New String() _
            {"Meatloaf", "Main Dish", boringMeatloaf, _
            boringMeatloafRanking}
        Dim row2 As String() = New String() _
            {"Key Lime Pie", "Dessert", _
            "lime juice, evaporated milk", _
            "****"}
        Dim row3 As String() = New String() _
            {"Orange-Salsa Pork Chops", "Main Dish", _
            "pork chops, salsa, orange juice", "****"}
        Dim row4 As String() = New String() _
            {"Black Bean and Rice Salad", "Salad", _
            "black beans, brown rice", _
            "****"}
        Dim row5 As String() = New String() _
            {"Chocolate Cheesecake", "Dessert", "cream cheese", _
            "***"}
        Dim row6 As String() = New String() _
            {"Black Bean Dip", "Appetizer", _
            "black beans, sour cream", _
                "***"}
        Dim rows As Object() = New Object() {row1, row2, _
            row3, row4, row5, row6}

        Dim rowArray As String()
        For Each rowArray In rows
            dataGridView.Rows.Add(rowArray)
        Next

        PostRowCreation()

        shortMode = False
        boringRecipe = True
    End Sub

    Protected Sub AddButton(ByVal button As Button, _
        ByVal buttonLabel As String)

        FlowLayoutPanel1.Controls.Add(button)
        button.TabIndex = FlowLayoutPanel1.Controls.Count
        button.Text = buttonLabel
        button.AutoSize = True
    End Sub

    ' Reset columns to initial disorderly arrangement.
    Private Sub ResetToDisorder(ByVal sender As Object, _
        ByVal e As System.EventArgs) _
        Handles Button1.Click
        Controls.Remove(dataGridview)
        dataGridView.Dispose()
        InitializeDataGridView(Nothing, Nothing)
    End Sub

    ' Change the header in column three.
    Private Sub Button2_Click(ByVal sender As Object, _
        ByVal e As System.EventArgs) _
        Handles Button2.Click

        Toggle(shortMode)
        If shortMode Then dataGridView.Columns(2).HeaderText = _
            "S" _
            Else dataGridView.Columns(2).HeaderText = _
                thirdColumnHeader
    End Sub

    Private Shared Sub Toggle(ByRef toggleThis As Boolean)
        toggleThis = Not toggleThis
    End Sub

    ' Change the meatloaf recipe.
    Private Sub Button3_Click(ByVal sender As Object, _
        ByVal e As System.EventArgs) _
        Handles Button3.Click

        Toggle(boringRecipe)
        If boringRecipe Then
            SetMeatloaf(boringMeatloaf, boringMeatloafRanking)
        Else
            Dim greatMeatloafRecipe As String = "1 lb. lean ground beef, " _
                & "1/2 cup bread crumbs, 1/4 cup ketchup," _
                & "1/3 tsp onion powder, " _
                & "1 clove of garlic, 1/2 pack onion soup mix " _
                & " dash of your favorite BBQ Sauce"
            SetMeatloaf(greatMeatloafRecipe, "***")
        End If
    End Sub

    Private Sub SetMeatloaf(ByVal recipe As String, _
        ByVal rating As String)

        dataGridView.Rows(0).Cells(2).Value = recipe
        dataGridView.Rows(0).Cells(3).Value = rating
    End Sub
#End Region

#Region "demonstration code"
    Private Sub AddAdditionalButtons()
        AddButton(Button4, "Freeze First Row")
        AddButton(Button5, "Freeze Second Column")
        AddButton(Button6, "Hide Salad Row")
        AddButton(Button7, "Disable First Column Resizing")
        AddButton(Button8, "Make ReadOnly")
        AddButton(Button9, "Style Using Tag")
    End Sub

    Private Sub AdjustDataGridViewSizing()
        dataGridView.AutoSizeRowsMode = _
            DataGridViewAutoSizeRowsMode.AllCells
        dataGridView.ColumnHeadersHeightSizeMode = _
            DataGridViewColumnHeadersHeightSizeMode.AutoSize
    End Sub

    ' Freeze the first row.
    Private Sub Button4_Click(ByVal sender As Object, _
        ByVal e As System.EventArgs) Handles Button4.Click

        FreezeBand(dataGridView.Rows(0))
    End Sub

    Private Sub FreezeColumn(ByVal sender As Object, _
        ByVal e As System.EventArgs) Handles Button5.Click

        FreezeBand(dataGridView.Columns(1))
    End Sub

    Private Shared Sub FreezeBand(ByVal band As DataGridViewBand)

        band.Frozen = True
        Dim style As DataGridViewCellStyle = New DataGridViewCellStyle()
        style.BackColor = Color.WhiteSmoke
        band.DefaultCellStyle = style

    End Sub

    ' Hide a band of cells.
    Private Sub Button6_Click(ByVal sender As Object, _
        ByVal e As System.EventArgs) Handles Button6.Click

        Dim band As DataGridViewBand = dataGridView.Rows(3)
        band.Visible = False
    End Sub

    ' Turn off user's ability to resize a column.
    Private Sub Button7_Click(ByVal sender As Object, _
        ByVal e As System.EventArgs) Handles Button7.Click

        Dim band As DataGridViewBand = dataGridView.Columns(0)
        band.Resizable = DataGridViewTriState.False
    End Sub

    ' Make the the entire DataGridView read only.
    Private Sub Button8_Click(ByVal sender As Object, _
        ByVal e As System.EventArgs) Handles Button8.Click

        For Each band As DataGridViewBand In dataGridView.Columns
            band.ReadOnly = True
        Next
    End Sub

    Private Sub PostRowCreation()
        SetBandColor(dataGridView.Columns(0), Color.CadetBlue)
        SetBandColor(dataGridView.Rows(1), Color.Coral)
        SetBandColor(dataGridView.Columns(2), Color.DodgerBlue)
    End Sub

    Private Shared Sub SetBandColor(ByVal band As DataGridViewBand, _
        ByVal color As Color)
        band.Tag = color
    End Sub

    ' Color the bands by the value stored in their tag.
    Private Sub Button9_Click(ByVal sender As Object, _
        ByVal e As System.EventArgs) Handles Button9.Click

        For Each band As DataGridViewBand In dataGridView.Columns
            If band.Tag IsNot Nothing Then
                band.DefaultCellStyle.BackColor = _
                    CType(band.Tag, Color)
            End If
        Next

        For Each band As DataGridViewBand In dataGridView.Rows
            If band.Tag IsNot Nothing Then
                band.DefaultCellStyle.BackColor = _
                    CType(band.Tag, Color)
            End If
        Next
    End Sub
#End Region

    <STAThreadAttribute()> _
    Public Shared Sub Main()
        Application.Run(New DataGridViewBandDemo())
    End Sub
End Class
using System.Drawing;
using System.Windows.Forms;
using System;

public class DataGridViewBandDemo : Form
{
    #region "form setup"
    public DataGridViewBandDemo()
    {
        InitializeComponent();

        AddButton(Button1, "Reset",
            new EventHandler(Button1_Click));
        AddButton(Button2, "Change Column 3 Header",
            new EventHandler(Button2_Click));
        AddButton(Button3, "Change Meatloaf Recipe",
            new EventHandler(Button3_Click));
        AddAdditionalButtons();

        InitializeDataGridView();
    }

    DataGridView dataGridView;
    Button Button1 = new Button();
    Button Button2 = new Button();
    Button Button3 = new Button();
    Button Button4 = new Button();
    Button Button5 = new Button();
    Button Button6 = new Button();
    Button Button7 = new Button();
    Button Button8 = new Button();
    Button Button9 = new Button();
    Button Button10 = new Button();
    FlowLayoutPanel FlowLayoutPanel1 = new FlowLayoutPanel();

    private void InitializeComponent()
    {
        FlowLayoutPanel1.Location = new Point(454, 0);
        FlowLayoutPanel1.AutoSize = true;
        FlowLayoutPanel1.FlowDirection = FlowDirection.TopDown;
        AutoSize = true;
        ClientSize = new System.Drawing.Size(614, 360);
        FlowLayoutPanel1.Name = "flowlayoutpanel";
        Controls.Add(this.FlowLayoutPanel1);
        Text = this.GetType().Name;
    }
    #endregion

    #region "setup DataGridView"

    private string thirdColumnHeader = "Main Ingredients";
    private string boringMeatloaf = "ground beef";
    private string boringMeatloafRanking = "*";
    private bool boringRecipe;
    private bool shortMode;

    private void InitializeDataGridView()
    {
        dataGridView = new System.Windows.Forms.DataGridView();
        Controls.Add(dataGridView);
        dataGridView.Size = new Size(300, 200);

        // Create an unbound DataGridView by declaring a
        // column count.
        dataGridView.ColumnCount = 4;
        AdjustDataGridViewSizing();

        // Set the column header style.
        DataGridViewCellStyle columnHeaderStyle =
            new DataGridViewCellStyle();
        columnHeaderStyle.BackColor = Color.Aqua;
        columnHeaderStyle.Font =
            new Font("Verdana", 10, FontStyle.Bold);
        dataGridView.ColumnHeadersDefaultCellStyle =
            columnHeaderStyle;

        // Set the column header names.
        dataGridView.Columns[0].Name = "Recipe";
        dataGridView.Columns[1].Name = "Category";
        dataGridView.Columns[2].Name = thirdColumnHeader;
        dataGridView.Columns[3].Name = "Rating";

        // Populate the rows.
        string[] row1 = new string[]{"Meatloaf", 
                                        "Main Dish", boringMeatloaf, boringMeatloafRanking};
        string[] row2 = new string[]{"Key Lime Pie", 
                                        "Dessert", "lime juice, evaporated milk", "****"};
        string[] row3 = new string[]{"Orange-Salsa Pork Chops", 
                                        "Main Dish", "pork chops, salsa, orange juice", "****"};
        string[] row4 = new string[]{"Black Bean and Rice Salad", 
                                        "Salad", "black beans, brown rice", "****"};
        string[] row5 = new string[]{"Chocolate Cheesecake", 
                                        "Dessert", "cream cheese", "***"};
        string[] row6 = new string[]{"Black Bean Dip", "Appetizer",
                                        "black beans, sour cream", "***"};
        object[] rows = new object[] { row1, row2, row3, row4, row5, row6 };

        foreach (string[] rowArray in rows)
        {
            dataGridView.Rows.Add(rowArray);
        }

        PostRowCreation();

        shortMode = false;
        boringRecipe = true;
    }


    void AddButton(Button button, string buttonLabel,
        EventHandler handler)
    {
        FlowLayoutPanel1.Controls.Add(button);
        button.TabIndex = FlowLayoutPanel1.Controls.Count;
        button.Text = buttonLabel;
        button.AutoSize = true;
        button.Click += handler;
    }

    // Reset columns to initial disorderly arrangement.
    private void Button1_Click(object sender, System.EventArgs e)
    {
        Controls.Remove(dataGridView);
        dataGridView.Dispose();
        InitializeDataGridView();
    }

    // Change the header in column three.
    private void Button2_Click(object sender,
        System.EventArgs e)
    {
        Toggle(ref shortMode);
        if (shortMode)
        { dataGridView.Columns[2].HeaderText = "S"; }
        else
        { dataGridView.Columns[2].HeaderText = thirdColumnHeader; }
    }

    private static void Toggle(ref bool toggleThis)
    {
        toggleThis = !toggleThis;
    }

    // Change the meatloaf recipe.
    private void Button3_Click(object sender,
        System.EventArgs e)
    {
        Toggle(ref boringRecipe);
        if (boringRecipe)
        {
            SetMeatloaf(boringMeatloaf, boringMeatloafRanking);
        }
        else
        {
            string greatMeatloafRecipe =
                "1 lb. lean ground beef, " +
                "1/2 cup bread crumbs, 1/4 cup ketchup," +
                "1/3 tsp onion powder, " +
                "1 clove of garlic, 1/2 pack onion soup mix " +
                " dash of your favorite BBQ Sauce";
            SetMeatloaf(greatMeatloafRecipe, "***");
        }
    }

    private void SetMeatloaf(string recipe, string rating)
    {
        dataGridView.Rows[0].Cells[2].Value = recipe;
        dataGridView.Rows[0].Cells[3].Value = rating;
    }
    #endregion

    #region "demonstration code"
    private void AddAdditionalButtons()
    {
        AddButton(Button4, "Freeze First Row",
            new EventHandler(Button4_Click));
        AddButton(Button5, "Freeze Second Column",
            new EventHandler(Button5_Click));
        AddButton(Button6, "Hide Salad Row",
            new EventHandler(Button6_Click));
        AddButton(Button7, "Disable First Column Resizing",
            new EventHandler(Button7_Click));
        AddButton(Button8, "Make ReadOnly",
            new EventHandler(Button8_Click));
        AddButton(Button9, "Style Using Tag",
            new EventHandler(Button9_Click));
    }

    private void AdjustDataGridViewSizing()
    {
        dataGridView.AutoSizeRowsMode =
            DataGridViewAutoSizeRowsMode.AllCells;
        dataGridView.ColumnHeadersHeightSizeMode = 
            DataGridViewColumnHeadersHeightSizeMode.AutoSize;
    }

    // Freeze the first row.
    private void Button4_Click(object sender, System.EventArgs e)
    {

        FreezeBand(dataGridView.Rows[0]);
    }

    private void Button5_Click(object sender, System.EventArgs e)
    {

        FreezeBand(dataGridView.Columns[1]);
    }

    private static void FreezeBand(DataGridViewBand band)
    {
        band.Frozen = true;
        DataGridViewCellStyle style = new DataGridViewCellStyle();
        style.BackColor = Color.WhiteSmoke;
        band.DefaultCellStyle = style;
    }

    // Hide a band of cells.
    private void Button6_Click(object sender, System.EventArgs e)
    {

        DataGridViewBand band = dataGridView.Rows[3];
        band.Visible = false;
    }

    // Turn off user's ability to resize a column.
    private void Button7_Click(object sender, EventArgs e)
    {

        DataGridViewBand band = dataGridView.Columns[0];
        band.Resizable = DataGridViewTriState.False;
    }

    // Make the the entire DataGridView read only.
    private void Button8_Click(object sender, System.EventArgs e)
    {
        foreach (DataGridViewBand band in dataGridView.Columns)
        {
            band.ReadOnly = true;
        }
    }

    private void PostRowCreation()
    {
        SetBandColor(dataGridView.Columns[0], Color.CadetBlue);
        SetBandColor(dataGridView.Rows[1], Color.Coral);
        SetBandColor(dataGridView.Columns[2], Color.DodgerBlue);
    }

    private static void SetBandColor(DataGridViewBand band, Color color)
    {
        band.Tag = color;
    }

    // Color the bands by the value stored in their tag.
    private void Button9_Click(object sender, System.EventArgs e)
    {

        foreach (DataGridViewBand band in dataGridView.Columns)
        {
            if (band.Tag != null)
            {
                band.DefaultCellStyle.BackColor = (Color)band.Tag;
            }
        }

        foreach (DataGridViewBand band in dataGridView.Rows)
        {
            if (band.Tag != null)
            {
                band.DefaultCellStyle.BackColor = (Color)band.Tag;
            }
        }
    }
    #endregion

    [STAThreadAttribute()]
    public static void Main()
    {
        Application.Run(new DataGridViewBandDemo());
    }
}

Compiling the Code

This example requires:

  • References to the System, System.Drawing, 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. 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

Reference

DataGridView
DataGridViewBand
DataGridViewRow
DataGridViewColumn

Other Resources

Programming with Cells, Rows, and Columns in the Windows Forms DataGridView Control