Code mẫu tham khảo:
' shamelessly adpated from an example at http://msdn.microsoft.com/en-us/magazine/cc163813.aspx
Public Class DataGridViewMaskedEditColumn
Inherits DataGridViewColumn
Private pPromptChar As Char = "_"c
Private pValidatingType As Type = GetType(String)
Private pMask As String = ""
Public Sub New()
MyBase.New(New DataGridViewMaskedEditCell())
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 MaskedEditCell
If Not (value Is Nothing) And Not value.GetType().IsAssignableFrom(GetType(DataGridViewMaskedEditCell)) Then
Throw New InvalidCastException("Must be a DataGridViewMaskedEditCell")
End If
MyBase.CellTemplate = value
End Set
End Property
'
' New properties required by the MaskedEditTextBox control
'
Public Property Mask() As String
Get
Return pMask
End Get
Set(ByVal value As String)
pMask = value
End Set
End Property
Public Property PromptChar() As Char
Get
Return pPromptChar
End Get
Set(ByVal value As Char)
pPromptChar = value
End Set
End Property
Public Property ValidatingType() As Type
Get
Return pValidatingType
End Get
Set(ByVal value As Type)
pValidatingType = value
End Set
End Property
End Class
Public Class DataGridViewMaskedEditCell
Inherits DataGridViewTextBoxCell
Dim pColumn As DataGridViewMaskedEditColumn
Public Sub New()
' nothing to do
End Sub
Public Overrides Sub InitializeEditingControl(ByVal rowIndex As Integer, ByVal initialFormattedValue As Object, ByVal dataGridViewCellStyle As DataGridViewCellStyle)
MyBase.InitializeEditingControl(rowIndex, initialFormattedValue, dataGridViewCellStyle)
pColumn = CType(Me.OwningColumn, DataGridViewMaskedEditColumn)
Dim ctl As MaskedEditEditingControl = CType(DataGridView.EditingControl, MaskedEditEditingControl)
' copy over the properties of the column
If Not IsNothing(Me.Value) Then
ctl.Text = Me.Value.ToString
Else
ctl.Text = ""
End If
ctl.ValidatingType = pColumn.ValidatingType
ctl.Mask = pColumn.Mask
ctl.PromptChar = pColumn.PromptChar
End Sub
Public Overrides ReadOnly Property EditType() As Type
Get
' Return the type of the editing contol
Return GetType(MaskedEditEditingControl)
End Get
End Property
Public Overrides ReadOnly Property ValueType() As Type
Get
' The validating type is set in the column class
Return pColumn.ValidatingType
End Get
End Property
Public Overrides ReadOnly Property DefaultNewRowValue() As Object
Get
Return ""
End Get
End Property
End Class
Class MaskedEditEditingControl
Inherits MaskedTextBox
Implements IDataGridViewEditingControl
Private dataGridViewControl As DataGridView
Private valueIsChanged As Boolean = False
Private rowIndexNum As Integer
Public Sub New()
' nothing to do
End Sub
Public Property EditingControlFormattedValue() As Object Implements IDataGridViewEditingControl.EditingControlFormattedValue
Get
Return Me.valueIsChanged.ToString
End Get
Set(ByVal value As Object)
If TypeOf value Is [String] Then
Me.Text = value.ToString
End If
End Set
End Property
Public Function GetEditingControlFormattedValue(ByVal context As DataGridViewDataErrorContexts) As Object Implements IDataGridViewEditingControl.GetEditingControlFormattedValue
Return Me.Text
End Function
Public Sub ApplyCellStyleToEditingControl(ByVal dataGridViewCellStyle As DataGridViewCellStyle) Implements IDataGridViewEditingControl.ApplyCellStyleToEditingControl
Me.Font = dataGridViewCellStyle.Font
Me.ForeColor = dataGridViewCellStyle.ForeColor
Me.BackColor = dataGridViewCellStyle.BackColor
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
Return True
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)
valueIsChanged = value
End Set
End Property
Public ReadOnly Property EditingPanelCursor() As Cursor Implements IDataGridViewEditingControl.EditingPanelCursor
Get
Return MyBase.Cursor
End Get
End Property
Protected Overrides Sub OnTextChanged(ByVal eventargs As EventArgs)
' Notify the DataGridView that the contents of the cell have changed.
valueIsChanged = True
Me.EditingControlDataGridView.NotifyCurrentCellDirty(True)
MyBase.OnTextChanged(eventargs)
End Sub
End Class