組合框在vb.net datagridview的未示出的值第一次

Question

以下是我的代碼：

Public Class Form1 

Private DT_LocalTransactionList As DataTable 

Private Sub DataGridView1_CellEnter(ByVal sender As Object, ByVal e As System.Windows.Forms.DataGridViewCellEventArgs) Handles DataGridView1.CellEnter 
    DT_LocalTransactionList = New DataTable 
    DT_LocalTransactionList.Columns.Add("TransactionName") 
    DT_LocalTransactionList.Columns.Add("TransactionType") 
    For iVisible As Integer = 0 To 5 
     DT_LocalTransactionList.Rows.Add() 
     DT_LocalTransactionList.Rows(iVisible).Item("TransactionName") = "Name " & iVisible 
     DT_LocalTransactionList.Rows(iVisible).Item("TransactionType") = "Add " & iVisible 
    Next 
    If e.ColumnIndex = colName.Index Then 
     Dim dgvCbo As New DataGridViewComboBoxCell 
     dgvCbo = TryCast(DataGridView1(colName.Index, e.RowIndex), DataGridViewComboBoxCell) 
     dgvCbo.DataSource = DT_LocalTransactionList 
     dgvCbo.DisplayMember = "TransactionName" 
     dgvCbo.ValueMember = "TransactionType" 
    End If 
End Sub 

Private Sub DataGridView1_EditingControlShowing(ByVal sender As System.Object, ByVal e As System.Windows.Forms.DataGridViewEditingControlShowingEventArgs) Handles DataGridView1.EditingControlShowing 
    Select Case Me.DataGridView1.CurrentCell.ColumnIndex 

     Case colName.Index 
      If TypeOf e.Control Is ComboBox Then 
       Dim cb As ComboBox = TryCast(e.Control, ComboBox) 
       cb.DropDownStyle = ComboBoxStyle.DropDown 
       cb.AutoCompleteSource = AutoCompleteSource.ListItems 
       cb.AutoCompleteMode = AutoCompleteMode.Suggest 
       RemoveHandler cb.DrawItem, AddressOf GridCombo_DrawItem 
       RemoveHandler cb.DropDownClosed, AddressOf cbDropDownClosed 
       RemoveHandler cb.Validating, AddressOf GridCombo_Validating 
       RemoveHandler cb.KeyDown, AddressOf GridCombo_KeyDown 
       AddHandler cb.DrawItem, AddressOf GridCombo_DrawItem 
       cb.DrawMode = DrawMode.OwnerDrawFixed 
       AddHandler cb.DropDownClosed, AddressOf cbDropDownClosed 
       AddHandler cb.Validating, AddressOf GridCombo_Validating 
       AddHandler cb.KeyDown, AddressOf GridCombo_KeyDown 
      End If 
    End Select 
End Sub 

Private Sub GridCombo_DrawItem(ByVal sender As System.Object, ByVal e As System.Windows.Forms.DrawItemEventArgs) 
    Dim text As String = sender.GetItemText(sender.Items(e.Index)) 

    e.DrawBackground() 

    Using br As New SolidBrush(e.ForeColor) 
     e.Graphics.DrawString(text, e.Font, Brushes.Black, e.Bounds) 
    End Using 

    e.DrawFocusRectangle() 
End Sub 

Private Sub cbDropDownClosed(ByVal sender As Object, ByVal e As System.EventArgs) 

End Sub 

Private Sub GridCombo_Validating(ByVal sender As Object, ByVal e As System.ComponentModel.CancelEventArgs) 
    Dim cb As ComboBox = TryCast(sender, ComboBox) 

    If Not IsItemExistInList(cb) Then 
     e.Cancel = True 
    End If 
End Sub 

Private Sub GridCombo_KeyDown(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyEventArgs) 
    Dim cb As ComboBox = TryCast(sender, ComboBox) 
    cb.Refresh() 

    If e.KeyCode = Keys.Enter Then 
     If IsItemExistInList(cb) Then 
      System.Windows.Forms.SendKeys.Send("{TAB}") 
     End If 
    End If 
End Sub 

Public Function IsItemExistInList(ByRef cboCombo As ComboBox) As Boolean 
    Dim blnContinue As Boolean 
    Dim intCount As Integer 

    blnContinue = False 

    If cboCombo.Text.Trim = "" Then 
     blnContinue = True 
    End If 

    If blnContinue = False Then 
     For intCount = 0 To cboCombo.Items.Count - 1 And blnContinue = False 
      If cboCombo.Text.Trim = cboCombo.GetItemText(cboCombo.Items(intCount)).Trim Then 
       blnContinue = True 
      End If 
     Next 
    End If 

    IsItemExistInList = blnContinue 
End Function 

    End Class 

當我輸入的datagridview的組合框控件「N」然後將其示出了來自自動填充功能的所有的值，然後選擇一個和按下標籤它不會顯示該字段中的選定值。當第二次做同樣的事情時，它顯示正確的選擇。如何在第一時間執行該事情？

Answer 1

一旦編輯控件按照指定的標準進行驗證，您應該查看CommitEdit DataGridView的方法。

Private Sub GridCombo_Validating(ByVal sender As Object, ByVal e As System.ComponentModel.CancelEventArgs) 
    Dim cb As ComboBox = TryCast(sender, ComboBox) 

    If Not IsItemExistInList(cb) Then 
     e.Cancel = True 
    Else 
     DataGridView1.CommitEdit(DataGridViewDataErrorContexts.CurrentCellChange) 
    End If 
End Sub 

在這種情況下，你可以忽略CommitEdit方法的返回值，因爲所提供的樣本只允許從收藏價值。所以如果價值不存在，單元格將不會被填充。

推薦read

與DataGridViewComboBoxColumn的工作，它需要2-3點擊以編輯該單元格的值，同時我也遇到過。我建議使用：

DataGridView1.EditMode = DataGridViewEditMode.EditOnEnter 

在某些起點。上面的代碼本身闡述了它的功能。