Imports System
Imports System.Windows.Forms
Public Class CalendarColumn
Inherits DataGridViewColumn
Public Sub New()
MyBase.New(New CalendarCell())
End Sub
Public Overrides Property CellTemplate() As DataGridViewCell
Get
Return MyBase.CellTemplate
End Get
Set(ByVal value As DataGridViewCell)
' Ensure that the cell used for the template is a CalendarCell.
If (value IsNot Nothing) AndAlso _
Not value.GetType().IsAssignableFrom(GetType(CalendarCell)) _
Then
Throw New InvalidCastException("Must be a CalendarCell")
End If
MyBase.CellTemplate = value
End Set
End Property
End Class
Public Class CalendarCell
Inherits DataGridViewTextBoxCell
Private isNullable As Boolean = False
Public Sub New()
' Use the short date format.
Me.Style.Format = "dd-MMM-yyyy"
End Sub
Public Sub New(ByVal isNullable As Boolean)
Me.New()
Me.isNullable = isNullable
End Sub
Public Overrides Sub InitializeEditingControl(ByVal rowIndex As Integer, _
ByVal initialFormattedValue As Object, _
ByVal dataGridViewCellStyle As DataGridViewCellStyle)
' Set the value of the editing control to the current cell value.
MyBase.InitializeEditingControl(rowIndex, initialFormattedValue, _
dataGridViewCellStyle)
If Not (Me.Value Is Nothing) And Not (Me.Value Is System.DBNull.Value) Then
Dim ctl As CalendarEditingControl = _
CType(DataGridView.EditingControl, CalendarEditingControl)
'ctl.Value = CType(Me.Value, DateTime)
ctl.ShowCheckBox = Me.isNullable
If Me.Value IsNot Nothing AndAlso Me.Value IsNot DBNull.Value Then
If TypeOf Me.Value Is DateTime Then
ctl.Checked = True '
ctl.Value = DirectCast(Me.Value, DateTime)
Else
Dim dtVal As DateTime
If DateTime.TryParse(Convert.ToString(Me.Value), dtVal) Then
ctl.Value = dtVal
End If
End If
If Me.isNullable Then
ctl.Checked = True
End If
ElseIf Me.isNullable Then
ctl.Checked = False
End If
End If
End Sub
Public Overrides ReadOnly Property EditType() As Type
Get
' Return the type of the editing contol that CalendarCell uses.
Return GetType(CalendarEditingControl)
End Get
End Property
Public Overrides ReadOnly Property ValueType() As Type
Get
' Return the type of the value that CalendarCell contains.
Return GetType(DateTime)
End Get
End Property
Public Overrides ReadOnly Property DefaultNewRowValue() As Object
Get
' Use the current date and time as the default value.
If Me.isNullable Then
Return Nothing
Else
Return Nothing
Return Format(DateTime.Now, "dd-MMM-yyy")
End If
End Get
End Property
End Class
Class CalendarEditingControl
Inherits DateTimePicker
Implements IDataGridViewEditingControl
Private dataGridViewControl As DataGridView
Private valueIsChanged As Boolean = False
Private rowIndexNum As Integer
'Public Sub New()
' Me.Format = DateTimePickerFormat.Short
'End Sub
Public Property EditingControlFormattedValue() As Object _
Implements IDataGridViewEditingControl.EditingControlFormattedValue
Get
If Me.ShowCheckBox AndAlso Not Me.Checked Then
Return [String].Empty
Else
If Me.Format = DateTimePickerFormat.[Custom] Then
Return Me.Value.ToString()
Else
Return Me.Value.ToShortDateString()
End If
End If
End Get
Set(ByVal value As Object)
Dim newValue As String = TryCast(value, String)
If Not [String].IsNullOrEmpty(newValue) Then
Me.Value = DateTime.Parse(newValue)
ElseIf Me.ShowCheckBox Then
Me.Checked = False
End If
End Set
End Property
Public Function GetEditingControlFormattedValue(ByVal context _
As DataGridViewDataErrorContexts) As Object _
Implements IDataGridViewEditingControl.GetEditingControlFormattedValue
Return Me.Value.ToShortDateString()
End Function
Public Sub ApplyCellStyleToEditingControl(ByVal dataGridViewCellStyle As _
DataGridViewCellStyle) _
Implements IDataGridViewEditingControl.ApplyCellStyleToEditingControl
Me.Font = dataGridViewCellStyle.Font
Me.CalendarForeColor = dataGridViewCellStyle.ForeColor
Me.CalendarMonthBackground = dataGridViewCellStyle.BackColor
Me.ShowCheckBox = True '
Me.Checked = False '
End Sub
Public Property EditingControlRowIndex() As Integer _
Implements IDataGridViewEditingControl.EditingControlRowIndex
Get
Return rowIndexNum
End Get
Set(ByVal value As Integer)
rowIndexNum = value
End Set
End Property
Public Function EditingControlWantsInputKey(ByVal key As Keys, _
ByVal dataGridViewWantsInputKey As Boolean) As Boolean _
Implements IDataGridViewEditingControl.EditingControlWantsInputKey
' Let the DateTimePicker handle the keys listed.
Select Case key And Keys.KeyCode
Case Keys.Left, Keys.Up, Keys.Down, Keys.Right, _
Keys.Home, Keys.End, Keys.PageDown, Keys.PageUp
Return True
Case Else
Return False
End Select
End Function
Public Sub PrepareEditingControlForEdit(ByVal selectAll As Boolean) _
Implements IDataGridViewEditingControl.PrepareEditingControlForEdit
' No preparation needs to be done.
End Sub
Public ReadOnly Property RepositionEditingControlOnValueChange() _
As Boolean Implements _
IDataGridViewEditingControl.RepositionEditingControlOnValueChange
Get
Return False
End Get
End Property
Public Property EditingControlDataGridView() As DataGridView _
Implements IDataGridViewEditingControl.EditingControlDataGridView
Get
Return dataGridViewControl
End Get
Set(ByVal value As DataGridView)
dataGridViewControl = value
End Set
End Property
Public Property EditingControlValueChanged() As Boolean _
Implements IDataGridViewEditingControl.EditingControlValueChanged
Get
Return valueIsChanged
End Get
Set(ByVal value As Boolean)
If valueIsChanged = True And Me.Checked = True Then
valueIsChanged = value
ElseIf valueIsChanged = False And Me.Checked = False Then
valueIsChanged = value
End If
End Set
End Property
Public ReadOnly Property EditingControlCursor() As Cursor _
Implements IDataGridViewEditingControl.EditingPanelCursor
Get
Return MyBase.Cursor
End Get
End Property
Protected Overrides Sub OnValueChanged(ByVal eventargs As EventArgs)
' Notify the DataGridView that the contents of the cell have changed.
If Me.Checked = True Then
valueIsChanged = True
ElseIf Me.Checked = False Then
valueIsChanged = False
End If
Me.EditingControlDataGridView.NotifyCurrentCellDirty(True)
MyBase.OnValueChanged(eventargs)
End Sub
End Class
|
