Visual Basic

<br />
Option Strict Off<br />
Option Explicit On <br />
<br />
Imports Microsoft.VisualBasic<br />
Imports System<br />
Imports System.ComponentModel<br />
Imports System.Data<br />
Imports System.Data.Common<br />
Imports System.Data.OleDb<br />
Imports System.Drawing<br />
Imports System.Windows.Forms<br />
<br />
Namespace DataGridTextBoxCombo<br />
    ' Step 1. Derive a custom column style from DataGridTextBoxColumn<br />
    '	a) add a ComboBox member<br />
    '  b) track when the combobox has focus in Enter and Leave events<br />
    '  c) override Edit to allow the ComboBox to replace the TextBox<br />
    '  d) override Commit to save the changed data<br />
    Public Class DataGridComboBoxColumn<br />
        Inherits DataGridTextBoxColumn<br />
        Public WithEvents ColumnComboBox As NoKeyUpCombo<br />
        Private _source As System.Windows.Forms.CurrencyManager<br />
        Private _rowNum As Integer<br />
        Private _isEditing As Boolean<br />
        Public Shared _RowCount As Integer<br />
<br />
<br />
        Public Sub New()<br />
            _source = Nothing<br />
            _isEditing = False<br />
            _RowCount = -1<br />
<br />
            ColumnComboBox = New NoKeyUpCombo<br />
            ColumnComboBox.DropDownStyle = ComboBoxStyle.DropDown<br />
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            AddHandler ColumnComboBox.SelectionChangeCommitted, AddressOf ComboStartEditing<br />
        End Sub 'New<br />
<br />
        Private Sub HandleScroll(ByVal sender As Object, ByVal e As EventArgs)<br />
            If ColumnComboBox.Visible Then<br />
                ColumnComboBox.Hide()<br />
            End If<br />
        End Sub 'HandleScroll<br />
<br />
        Private Sub ComboStartEditing(ByVal sender As Object, ByVal e As EventArgs)<br />
            _isEditing = True<br />
            MyBase.ColumnStartedEditing(sender)<br />
        End Sub 'ComboMadeCurrent<br />
<br />
<br />
        Private Sub CompletionCombo_Leave(ByVal sender As Object, ByVal e As System.EventArgs) Handles ColumnComboBox.Leave<br />
            If _isEditing Or ColumnComboBox._isEditing Then<br />
                SetColumnValueAtRow(_source, _rowNum, ColumnComboBox.Text)<br />
                _isEditing = False<br />
                Invalidate()<br />
<br />
            End If<br />
            ColumnComboBox.Hide()<br />
            AddHandler Me.DataGridTableStyle.DataGrid.Scroll, New EventHandler(AddressOf HandleScroll)<br />
        End Sub 'LeaveComboBox<br />
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<br />
        Protected Overloads Overrides Sub Edit(ByVal [source] As System.Windows.Forms.CurrencyManager, ByVal rowNum As Integer, ByVal bounds As System.Drawing.Rectangle, ByVal [readOnly] As Boolean, ByVal instantText As String, ByVal cellIsVisible As Boolean)<br />
<br />
            MyBase.Edit([source], rowNum, bounds, [readOnly], instantText, cellIsVisible)<br />
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            '_isEditing = True<br />
            _rowNum = rowNum<br />
            _source = [source]<br />
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            ColumnComboBox.Parent = Me.TextBox.Parent<br />
            ColumnComboBox.Location = Me.TextBox.Location<br />
            ColumnComboBox.Size = New Size(Me.TextBox.Size.Width, ColumnComboBox.Size.Height)<br />
            'ColumnComboBox.SelectedIndex = ColumnComboBox.FindStringExact(Me.TextBox.Text)<br />
            ColumnComboBox.Text = Me.TextBox.Text<br />
            Me.TextBox.Visible = False<br />
            ColumnComboBox.Visible = True<br />
            AddHandler Me.DataGridTableStyle.DataGrid.Scroll, AddressOf HandleScroll<br />
<br />
            ColumnComboBox.BringToFront()<br />
            ColumnComboBox.Focus()<br />
        End Sub 'Edit<br />
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<br />
        Protected Overrides Function Commit(ByVal dataSource As System.Windows.Forms.CurrencyManager, ByVal rowNum As Integer) As Boolean<br />
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            If _isEditing Then<br />
                _isEditing = False<br />
                SetColumnValueAtRow(dataSource, rowNum, ColumnComboBox.Text)<br />
            End If<br />
            Return True<br />
        End Function 'Commit<br />
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<br />
        Protected Overrides Sub ConcedeFocus()<br />
            Console.WriteLine("ConcedeFocus")<br />
            MyBase.ConcedeFocus()<br />
        End Sub 'ConcedeFocus<br />
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        Protected Overrides Function GetColumnValueAtRow(ByVal [source] As System.Windows.Forms.CurrencyManager, ByVal rowNum As Integer) As Object<br />
<br />
            Dim s As Object = MyBase.GetColumnValueAtRow([source], rowNum)<br />
            Dim dv As DataView = CType(Me.ColumnComboBox.DataSource, DataView)<br />
            Dim rowCount As Integer = dv.Count<br />
            Dim i As Integer = 0<br />
            Dim s1 As Object<br />
<br />
            'if things are slow, you could order your dataview<br />
            '& use binary search instead of this linear one<br />
            While i < rowCount<br />
                s1 = dv(i)(Me.ColumnComboBox.ValueMember)<br />
                If (Not s1 Is DBNull.Value) AndAlso _<br />
                    (Not s Is DBNull.Value) AndAlso _<br />
                            s = s1 Then<br />
                    Exit While<br />
                End If<br />
                i = i + 1<br />
            End While<br />
<br />
            If i < rowCount Then<br />
                Return dv(i)(Me.ColumnComboBox.DisplayMember)<br />
            End If<br />
            Return DBNull.Value<br />
        End Function 'GetColumnValueAtRow<br />
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        Protected Overrides Sub SetColumnValueAtRow(ByVal [source] As System.Windows.Forms.CurrencyManager, ByVal rowNum As Integer, ByVal value As Object)<br />
            Dim s As Object = value<br />
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            Dim dv As DataView = CType(Me.ColumnComboBox.DataSource, DataView)<br />
            Dim rowCount As Integer = dv.Count<br />
            Dim i As Integer = 0<br />
            Dim s1 As Object<br />
<br />
            'if things are slow, you could order your dataview<br />
            '& use binary search instead of this linear one<br />
            While i < rowCount<br />
                s1 = dv(i)(Me.ColumnComboBox.DisplayMember)<br />
                If (Not s1 Is DBNull.Value) AndAlso _<br />
                            s = s1 Then<br />
                    Exit While<br />
                End If<br />
                i = i + 1<br />
            End While<br />
            If i < rowCount Then<br />
                s = dv(i)(Me.ColumnComboBox.ValueMember)<br />
            Else<br />
                s = DBNull.Value<br />
            End If<br />
            MyBase.SetColumnValueAtRow([source], rowNum, s)<br />
        End Sub 'SetColumnValueAtRow <br />
<br />
    End Class 'DataGridComboBoxColumn<br />
<br />
<br />
End Namespace<br />

<br />
Option Strict Off<br />
Option Explicit On <br />
<br />
Imports Microsoft.VisualBasic<br />
Imports System<br />
Imports System.ComponentModel<br />
Imports System.Data<br />
Imports System.Data.Common<br />
Imports System.Data.OleDb<br />
Imports System.Drawing<br />
Imports System.Windows.Forms<br />
<br />
Namespace DataGridTextBoxCombo<br />
    Public Class NoKeyUpCombo<br />
        Inherits ComboBox<br />
        Private WM_KEYUP As Integer = &H101<br />
        Public _isEditing As Boolean = False<br />
        <br />
        Protected Overrides Sub WndProc(ByRef m As System.Windows.Forms.Message)<br />
            If m.Msg = WM_KEYUP Then<br />
                'ignore keyup to avoid problem with tabbing & dropdownlist;<br />
                Return<br />
            End If<br />
            MyBase.WndProc(m)<br />
        End Sub 'WndProc<br />
<br />
        Protected Overrides Sub OnEnter(ByVal e As System.EventArgs)<br />
            _isEditing = True<br />
            MyBase.Focus()<br />
        End Sub<br />
<br />
        Private Sub CompletionCombo_KeyUp(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyEventArgs) Handles MyBase.KeyUp<br />
            Dim sTypedText As String<br />
            Dim iFoundIndex As Integer<br />
            Dim oFoundItem As Object<br />
            Dim sFoundText As String<br />
            Dim sAppendText As String<br />
<br />
            If Me.Items.Count > 0 Then<br />
                'Allow select keys without Autocompleting<br />
                Select Case e.KeyCode<br />
                    Case Keys.Back, Keys.Left, Keys.Right, Keys.Up, Keys.Delete, Keys.Down, Keys.ControlKey, Keys.ShiftKey, Keys.Alt, Keys.ShiftKey, Keys.MButton, Keys.LButton, Keys.RButton, Keys.Home, Keys.End<br />
                        'e.Handled = False<br />
                        Exit Sub<br />
                End Select<br />
<br />
                'Get the Typed Text and Find it in the list<br />
                If Me.Text.Length > 0 And Me.Text.Length <> Me.SelectedText.Length Then<br />
                    sTypedText = Me.Text<br />
                    iFoundIndex = Me.FindString(sTypedText)<br />
<br />
                    'If we found the Typed Text in the list then Autocomplete<br />
                    If iFoundIndex >= 0 Then<br />
                        'Get the Item from the list (Return Type depends if Datasource was bound <br />
                        ' or List Created)<br />
                        oFoundItem = Me.Items(iFoundIndex)<br />
<br />
                        'Use the ListControl.GetItemText to resolve the Name in case the Combo <br />
                        ' was Data bound<br />
                        sFoundText = Me.GetItemText(oFoundItem)<br />
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                        'Append then found text to the typed text to preserve case<br />
                        sAppendText = sFoundText.Substring(sTypedText.Length)<br />
                        Me.Text = sTypedText & sAppendText<br />
<br />
                        'Select the Appended Text<br />
                        Me.SelectionStart = sTypedText.Length<br />
                        Me.SelectionLength = sAppendText.Length<br />
                        'Me.SelectedIndex = iFoundIndex<br />
                    End If<br />
                End If<br />
            End If<br />
<br />
        End Sub<br />
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        Private Sub CompletionCombo_Leave(ByVal sender As Object, ByVal e As System.EventArgs) Handles MyBase.Leave<br />
            Dim iFoundIndex As Integer<br />
<br />
            If Me.Items.Count > 0 Then<br />
                Dim sFoundText As String = ""<br />
                If Me.SelectedText.Length <> Me.Text.Length Then<br />
                    sFoundText = Me.Text.Substring(Me.SelectedText.Length, Me.Text.Length)<br />
                End If<br />
                If sFoundText.Length > 0 Then<br />
                    iFoundIndex = Me.FindString(Me.Text)<br />
<br />
                    Me.SelectedIndex = iFoundIndex<br />
                End If<br />
            End If<br />
<br />
            ' Now ask to make a new address, if there is no autocomplete.<br />
            If MyBase.SelectedIndex = -1 And MyBase.Text.Length > 0 Then<br />
                If MessageBox.Show("Cannot find item: '" & MyBase.Text & "'." & vbCrLf & "Would you like to create a new item?", "Create a New Entry?", MessageBoxButtons.YesNo, MessageBoxIcon.Question) = DialogResult.Yes Then<br />
                    ' TODO: Add code to make a new inventory item.<br />
                Else<br />
                    MyBase.Text = ""<br />
                    MyBase.Focus()<br />
                End If<br />
            End If<br />
        End Sub<br />
    End Class 'NoKeyUpCombo<br />
End Namespace<br />
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