Normally the DataGridView control does not support adding a checkbox in the header cell.
But this doesn’t mean that it is impossible. You can create your own class that inherits from the DataGridViewColumnHeaderCell and use it.
Here’s one class I had created for myself when I needed it. Besides putting the CheckBox in the header cell, it also has a couple of properties and methods to make it behave the way we are used to seeing in normal windows applications. You can modify it as per your needs.
Imports System
Imports System.Drawing
Imports System.Windows.Forms
Imports System.Windows.Forms.VisualStyles
Imports System.ComponentModel
Public Class DataGridViewCheckBoxHeaderCell
Inherits DataGridViewColumnHeaderCell
Private CheckBoxBounds As Rectangle
Private CellLocation As New Point()
Private CheckBoxState As CheckBoxState
Public Delegate Sub DataGridViewCheckBoxHeaderCellEventHandler(ByVal sender As Object, ByVal e As DataGridViewCheckBoxHeaderCellEventArgs)
Public Event CheckBoxClicked As DataGridViewCheckBoxHeaderCellEventHandler
#Region "Properties"
Private _CheckBoxAlignment As HorizontalAlignment = HorizontalAlignment.Center
Public Property CheckBoxAlignment() As HorizontalAlignment
Get
Return _CheckBoxAlignment
End Get
Set(ByVal value As HorizontalAlignment)
If Not [Enum].IsDefined(GetType(HorizontalAlignment), value) Then
Throw New InvalidEnumArgumentException("value", CInt(value), GetType(HorizontalAlignment))
End If
If _CheckBoxAlignment <> value Then
_CheckBoxAlignment = value
If Me.DataGridView IsNot Nothing Then Me.DataGridView.InvalidateCell(Me)
End If
End Set
End Property
Private _Checked As Boolean
Public Property Checked() As Boolean
Get
Return _Checked
End Get
Set(ByVal value As Boolean)
'If _Checked <> value Then
_Checked = value
CheckState = IIf(_Checked, CheckState.Checked, CheckState.Unchecked)
If Me.DataGridView IsNot Nothing Then Me.DataGridView.InvalidateCell(Me)
'End If
End Set
End Property
Public Property CheckState() As CheckState
Get
Select Case CheckBoxState
Case CheckBoxState.CheckedDisabled, CheckBoxState.CheckedHot, CheckBoxState.CheckedNormal, CheckBoxState.CheckedPressed
Return CheckState.Checked
Case CheckBoxState.UncheckedDisabled, CheckBoxState.UncheckedHot, CheckBoxState.UncheckedNormal, CheckBoxState.UncheckedPressed
Return CheckState.Unchecked
Case CheckBoxState.MixedDisabled, CheckBoxState.MixedHot, CheckBoxState.MixedNormal, CheckBoxState.MixedPressed
Return CheckState.Indeterminate
End Select
End Get
Set(ByVal value As CheckState)
If CheckState <> value Then
If MyBase.DataGridView IsNot Nothing AndAlso MyBase.DataGridView.Enabled Then
'enabled state
Select Case value
Case CheckState.Checked
CheckBoxState = CheckBoxState.CheckedNormal
_Checked = True
Case CheckState.Indeterminate
CheckBoxState = CheckBoxState.MixedNormal
Case CheckState.Unchecked
CheckBoxState = CheckBoxState.UncheckedNormal
_Checked = False
End Select
Else
'disabled state
Select Case value
Case CheckState.Checked
CheckBoxState = CheckBoxState.CheckedDisabled
_Checked = True
Case CheckState.Indeterminate
CheckBoxState = CheckBoxState.MixedDisabled
Case CheckState.Unchecked
CheckBoxState = CheckBoxState.UncheckedDisabled
_Checked = False
End Select
End If
If Me.DataGridView IsNot Nothing Then Me.DataGridView.InvalidateCell(Me)
End If
End Set
End Property
#End Region
#Region "Methods"
Protected Overridable Sub OnCheckBoxClicked(ByVal e As DataGridViewCheckBoxHeaderCellEventArgs)
RaiseEvent CheckBoxClicked(Me, e)
End Sub
Public Sub CheckUncheckEntireColumn(ByVal checked As Boolean)
Me.DataGridView.SuspendLayout()
For Each row As DataGridViewRow In Me.DataGridView.Rows
row.Cells(Me.ColumnIndex).Value = checked
Next
Me.DataGridView.ResumeLayout(True)
Me.DataGridView.RefreshEdit()
End Sub
Public Sub RefreshCheckState()
Dim newState As Boolean = Me.DataGridView.Rows(0).Cells(Me.ColumnIndex).EditedFormattedValue
For Each row As DataGridViewRow In Me.DataGridView.Rows
If row.Cells(Me.ColumnIndex).EditedFormattedValue <> newState Then
Me.CheckState = CheckState.Indeterminate
Exit Sub
End If
Next
Me.Checked = newState
End Sub
#End Region
#Region "Override"
Protected Overloads Overrides Sub Paint(ByVal graphics As Graphics, ByVal clipBounds As Rectangle, ByVal cellBounds As Rectangle, ByVal rowIndex As Integer, ByVal dataGridViewElementState As DataGridViewElementStates, ByVal value As Object, _
ByVal formattedValue As Object, ByVal errorText As String, ByVal cellStyle As DataGridViewCellStyle, ByVal advancedBorderStyle As DataGridViewAdvancedBorderStyle, ByVal paintParts As DataGridViewPaintParts)
'checkbox bounds
Dim state As CheckBoxState = Me.CheckBoxState
Dim checkBoxSize As Size
Dim checkBoxLocation As Point
cellLocation = cellBounds.Location
checkBoxSize = CheckBoxRenderer.GetGlyphSize(graphics, state)
Dim p As New Point()
p.Y = cellBounds.Location.Y + (cellBounds.Height / 2) - (checkBoxSize.Height / 2)
Select Case Me.CheckBoxAlignment
Case HorizontalAlignment.Center
p.X = cellBounds.Location.X + (cellBounds.Width / 2) - (checkBoxSize.Width / 2) - 1
Case HorizontalAlignment.Left
p.X = cellBounds.Location.X + 2
Case HorizontalAlignment.Right
p.X = cellBounds.Right - checkBoxSize.Width - 4
End Select
checkBoxLocation = p
checkBoxBounds = New Rectangle(checkBoxLocation, checkBoxSize)
'paint background
paintParts = paintParts And Not DataGridViewPaintParts.ContentForeground
MyBase.Paint(graphics, clipBounds, cellBounds, rowIndex, dataGridViewElementState, value, formattedValue, errorText, cellStyle, advancedBorderStyle, paintParts)
'paint foreground
Select Case Me.CheckBoxAlignment
Case HorizontalAlignment.Center
cellBounds.Width = checkBoxLocation.X - cellBounds.X - 2
Case HorizontalAlignment.Left
cellBounds.X += checkBoxSize.Width + 2
cellBounds.Width -= checkBoxSize.Width + 2
Case HorizontalAlignment.Right
cellBounds.Width -= checkBoxSize.Width + 4
End Select
paintParts = DataGridViewPaintParts.ContentForeground
MyBase.Paint(graphics, clipBounds, cellBounds, rowIndex, dataGridViewElementState, value, "", errorText, cellStyle, advancedBorderStyle, paintParts)
'paint check box
CheckBoxRenderer.DrawCheckBox(graphics, checkBoxLocation, state)
End Sub
Protected Overloads Overrides Sub OnMouseClick(ByVal e As DataGridViewCellMouseEventArgs)
If e.Button = MouseButtons.Left Then
'click on check box ?
Dim p As New Point(cellLocation.X + e.X, cellLocation.Y + e.Y)
If checkBoxBounds.Contains(p) Then
'raise event
RaiseCheckBoxClicked()
End If
End If
MyBase.OnMouseClick(e)
End Sub
Protected Overloads Overrides Sub OnKeyDown(ByVal e As KeyEventArgs, ByVal rowIndex As Integer)
If e.KeyCode = Keys.Space Then
'raise event
RaiseCheckBoxClicked()
End If
MyBase.OnKeyDown(e, rowIndex)
End Sub
Public Overloads Overrides Function Clone() As Object
Dim cell As DataGridViewCheckBoxHeaderCell = TryCast(MyBase.Clone(), DataGridViewCheckBoxHeaderCell)
If cell IsNot Nothing Then
cell.Checked = Me.Checked
End If
Return cell
End Function
#End Region
#Region "Private"
Private Sub RaiseCheckBoxClicked()
'raise event
Dim e As New DataGridViewCheckBoxHeaderCellEventArgs(Not Me.Checked)
Me.OnCheckBoxClicked(e)
If Not e.Cancel Then
Me.Checked = e.Checked
Me.DataGridView.InvalidateCell(Me)
End If
End Sub
#End Region
End Class
#Region "EventArgs Class"
Public Class DataGridViewCheckBoxHeaderCellEventArgs
Inherits CancelEventArgs
Private _Checked As Boolean
Public ReadOnly Property Checked() As Boolean
Get
Return _Checked
End Get
End Property
Public Sub New(ByVal checkedValue As Boolean)
MyBase.New()
_Checked = checkedValue
End Sub
Public Sub New(ByVal checkedValue As Boolean, ByVal cancel As Boolean)
MyBase.New(cancel)
_Checked = checkedValue
End Sub
End Class
#End Region
Sample Usage
Add the above class to your project.
Add a DataGridView control (DataGridView1) to your form and the following code:
Public Class Form1
'' declare our header cell with checkbox
Dim WithEvents CheckBoxHeaderCell As DataGridViewCheckBoxHeaderCell
Private Sub Form3_Load(sender As System.Object, e As System.EventArgs) Handles MyBase.Load
'' some dummy data source
Dim di As New IO.DirectoryInfo("C:\")
Dim ds = From fi In di.GetFiles _
Select New With {.FileName = fi.Name, .CreationTime = fi.CreationTime, _
.LastAccessTime = fi.LastAccessTime, .LastModified = fi.LastWriteTime}
DataGridView1.DataSource = ds.ToList
DataGridView1.Columns.Insert(0, New DataGridViewCheckBoxColumn)
'' our checkbox in header cell
CheckBoxHeaderCell = New DataGridViewCheckBoxHeaderCell
DataGridView1.Columns(0).HeaderCell = CheckBoxHeaderCell
End Sub
Private Sub CheckBoxHeaderCell_CheckBoxClicked(sender As Object, e As DataGridViewCheckBoxHeaderCellEventArgs) Handles CheckBoxHeaderCell.CheckBoxClicked
CheckBoxHeaderCell.CheckUncheckEntireColumn(e.Checked)
End Sub
Private Sub DataGridView1_CellContentClick(sender As Object, e As System.Windows.Forms.DataGridViewCellEventArgs) Handles DataGridView1.CellContentClick
If e.ColumnIndex = CheckBoxHeaderCell.ColumnIndex Then CheckBoxHeaderCell.RefreshCheckState()
End Sub
End Class
Run the program.
