问题
I'm trying to make gridview Datetimepicker column and i succeeded, but i have a little problem that when the user edit the date in the gridview the date appear in short "11/9/16" but what i want is the date and the time together"11/9/16 2:34:45 AM"
This is the code I use:
CalendarColumn:
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
CalendarCell:
Public Class CalendarCell
Inherits DataGridViewTextBoxCell
Public Sub New()
' Use the short date format.
'Me.Style.Format = "d"
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)
Dim ctl As CalendarEditingControl = _
CType(DataGridView.EditingControl, CalendarEditingControl)
' Use the default row value when Value property is null.
If (Me.Value Is Nothing) Then
ctl.Value = CType(Me.DefaultNewRowValue, DateTime)
Else
ctl.Value = CType(Me.Value, DateTime)
End If
End Sub
Public Overrides ReadOnly Property EditType() As Type
Get
' Return the type of the editing control 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.
Return DateTime.Now
End Get
End Property
End Class
CalendarEditingControl:
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.Long
'Me.CustomFormat = "'Today is:' hh:mm:ss dddd MMMM dd, yyyy"
End Sub
Public Property EditingControlFormattedValue() As Object _
Implements IDataGridViewEditingControl.EditingControlFormattedValue
Get
Return Me.Value.ToShortDateString()
End Get
Set(ByVal value As Object)
Try
' This will throw an exception of the string is
' null, empty, or not in the format of a date.
Me.Value = DateTime.Parse(CStr(value))
Catch
' In the case of an exception, just use the default
' value so we're not left with a null value.
Me.Value = DateTime.Now
End Try
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
End Sub
And this code for add column :
Dim col As New CalendarColumn() With {.HeaderText = "Date time"}
DataGridView1.Columns.Insert(5, col)
source Code
How can I make it long with the time.
回答1:
To show a date and time in custom format, you should assign format to Format property of DefaultCellStyle. The CustomFormat property of DateTimePicker is useful for editing format but for displaying data in cell you should use column.DefaultCellStyle.Format.
For example to show date and time like 2016/09/15 10:31:04 PM you should use yyyy/MM/dd h:mm:ss tt as format.
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
Dim dt = New DataTable()
dt.Columns.Add("Date", GetType(DateTime))
dt.Rows.Add(DateTime.Now)
dt.Rows.Add(DateTime.Now)
Dim column = New DataGridViewTextBoxColumn()
column.DefaultCellStyle.Format = "yyyy/MM/dd h:mm:ss tt"
column.DataPropertyName = "Date"
Me.DataGridView1.Columns.Add(column)
Me.DataGridView1.DataSource = dt
End Sub
For more information about custom date formats see:
- Custom Date and Time Format Strings
DataGridView DateTimePicker Column
Here is the full source code of date time picker column with some fixes. The source has been taken from MSDN and I just made some small changes and a small fix. The changes has been made to support Time and long format. Also the fix has been done to prevent exception when the cell value is DBNull.Value:
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
Public Sub New()
' Use the short date format.
Me.Style.Format = "yyyy/MM/dd h:mm:ss tt"
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)
Dim ctl As CalendarEditingControl = _
CType(DataGridView.EditingControl, CalendarEditingControl)
' Use the default row value when Value property is null.
If (Me.Value Is Nothing OrElse IsDBNull(Me.Value)) Then
ctl.Value = CType(Me.DefaultNewRowValue, DateTime)
Else
ctl.Value = CType(Me.Value, DateTime)
End If
End Sub
Public Overrides ReadOnly Property EditType() As Type
Get
' Return the type of the editing control 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.
Return DateTime.Now
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.Custom
Me.CustomFormat = "yyyy/MM/dd h:mm:ss tt"
End Sub
Public Property EditingControlFormattedValue() As Object _
Implements IDataGridViewEditingControl.EditingControlFormattedValue
Get
Return Me.Value.ToString("yyyy/MM/dd h:mm:ss tt")
End Get
Set(ByVal value As Object)
Try
' This will throw an exception of the string is
' null, empty, or not in the format of a date.
Me.Value = DateTime.Parse(CStr(value))
Catch
' In the case of an exception, just use the default
' value so we're not left with a null value.
Me.Value = DateTime.Now
End Try
End Set
End Property
Public Function GetEditingControlFormattedValue(ByVal context _
As DataGridViewDataErrorContexts) As Object _
Implements IDataGridViewEditingControl.GetEditingControlFormattedValue
Return Me.Value.ToString("yyyy/MM/dd h:mm:ss tt")
End Function
Public Sub ApplyCellStyleToEditingControl(ByVal dataGridViewCellStyle As _
DataGridViewCellStyle) _
Implements IDataGridViewEditingControl.ApplyCellStyleToEditingControl
Me.Font = dataGridViewCellStyle.Font
Me.CalendarForeColor = dataGridViewCellStyle.ForeColor
Me.CalendarMonthBackground = 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
' 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 Not dataGridViewWantsInputKey
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)
valueIsChanged = value
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.
valueIsChanged = True
Me.EditingControlDataGridView.NotifyCurrentCellDirty(True)
MyBase.OnValueChanged(eventargs)
End Sub
End Class
And here is the test code:
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
Dim dt = New DataTable()
dt.Columns.Add("Date", GetType(DateTime))
dt.Rows.Add(DateTime.Now)
dt.Rows.Add(DateTime.Now)
Dim column = New CalendarColumn()
column.DataPropertyName = "Date"
Me.DataGridView1.Columns.Add(column)
Me.DataGridView1.DataSource = dt
End Sub
来源：https://stackoverflow.com/questions/39517130/datagridview-datetimepicker-column-add-long-format-support-date-and-the-time