ArgumentException lors de l'ajout de zone de liste déroulante de la colonne de DataGridView avec la même source de données

DataGridViewComboBoxColumn limites de saisie de valeurs dans la source de données. J'ai eu ce même problème. J'ai essayé de définir la valeur du champ à l'extérieur de la DGV. J'ai été liaison de la DGV à un DataTable. Si j'ai mis un DataRow["somefield"] pour une valeur de pas dans la source de données, je voudrais recevoir le message d'erreur que vous recevez.

J'ai finalement créé un descendant de DataGridViewColumn qui prennent en charge une zone de liste déroulante de l'éditeur et de permis pour les valeurs qui ne sont pas dans la source de données.

Je peux poster le code, si vous souhaitez le voir.

EDIT: Voici une liste déroulante de la colonne exemple

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.ComponentModel;
using System.Drawing;
using System.Windows.Forms.VisualStyles;
namespace YourNamespaceHere
{
///<summary>
///DataGridView TextBox column with Items support.
///</summary>
public class DropTextBoxColumn : DataGridViewColumn
{
[Browsable(false)]
public IEnumerable<string> Items { get; set; }
public ComboBoxStyle DropDownStyle { get; set; }
public DropTextBoxColumn() : base(new DropTextBoxCell()) 
{
DropDownStyle = ComboBoxStyle.DropDown;
}
private DataGridViewCell cellTemplate = new DropTextBoxCell();
public override DataGridViewCell CellTemplate
{
get
{
return cellTemplate;
}
set
{
//Ensure that the cell used for the template is a DropTextBoxCell.
if (value != null &&
!value.GetType().IsAssignableFrom(typeof(DropTextBoxCell)))
{
throw new InvalidCastException("Must be a DropTextBoxCell");
}
cellTemplate = value;
}
}
}
public class DropTextBoxCell : DataGridViewTextBoxCell
{
[Browsable(false)]
public string[] Items { get; set; }
public DropTextBoxCell() : base() { }
protected override void Paint(Graphics graphics, Rectangle clipBounds, Rectangle cellBounds, int rowIndex, DataGridViewElementStates cellState, object value, object formattedValue, string errorText, DataGridViewCellStyle cellStyle, DataGridViewAdvancedBorderStyle advancedBorderStyle, DataGridViewPaintParts paintParts)
{
base.Paint(graphics, clipBounds, cellBounds, rowIndex, cellState, value, formattedValue, errorText, cellStyle, advancedBorderStyle, paintParts);
//draw a drop down button
if ( (cellState & DataGridViewElementStates.Selected) != 0) 
{
var cb = cellBounds;
var r = new Rectangle(cb.Right - cb.Height, cb.Top, cb.Height, cb.Height);
//ComboBoxRenderer.DrawTextBox(graphics, cb, formattedValue as string, this.Style.Font ?? DataGridView.Font, ComboBoxState.Normal);
ComboBoxRenderer.DrawDropDownButton(graphics, r, ComboBoxState.Normal);            
}
}
public override void InitializeEditingControl(int rowIndex, object
initialFormattedValue, DataGridViewCellStyle dataGridViewCellStyle)
{
//Set the value of the editing control to the current cell value.
base.InitializeEditingControl(rowIndex, initialFormattedValue,
dataGridViewCellStyle);
DropTextBoxEditingControl ctl =
DataGridView.EditingControl as DropTextBoxEditingControl;
var value = this.Value.ToString();
ctl.Loading = true;
DropTextBoxColumn col = DataGridView.Columns[this.ColumnIndex] as DropTextBoxColumn;
ctl.DropDownStyle = col.DropDownStyle;
ctl.Items.Clear();
if (col.Items != null)
ctl.Items.AddRange(col.Items.ToArray());
ctl.EditingControlFormattedValue = value;
ctl.Loading = false;
}
public override Type EditType
{
get
{
//Return the type of the editing contol that CalendarCell uses.
return typeof(DropTextBoxEditingControl);
}
}
public override Type ValueType
{
get
{
//Return the type of the value that CalendarCell contains.
return typeof(string);
}
}
public override object DefaultNewRowValue
{
get
{
//Use the current date and time as the default value.
return string.Empty;
}
}
}
class DropTextBoxEditingControl : ComboBox, IDataGridViewEditingControl
{
DataGridView dataGridView;
private bool valueChanged = false;
int rowIndex;
public bool Loading { get; set; }
int originalIndex = -1;
public DropTextBoxEditingControl()
{
//this.Format = DateTimePickerFormat.Short;
DropDownStyle = ComboBoxStyle.DropDown;
FlatStyle = FlatStyle.Flat;     
}
//Implements the IDataGridViewEditingControl.EditingControlFormattedValue 
//property.
public object EditingControlFormattedValue
{
get
{
return Text;
}
set
{
if (value is String)
{
if (DropDownStyle == ComboBoxStyle.DropDown)
Text = value.ToString();
else
{
SelectedIndex = originalIndex = Items.IndexOf(value);                        
}                    
}
}
}
//Implements the 
//IDataGridViewEditingControl.GetEditingControlFormattedValue method.
public object GetEditingControlFormattedValue(
DataGridViewDataErrorContexts context)
{
return EditingControlFormattedValue;
}
//Implements the 
//IDataGridViewEditingControl.ApplyCellStyleToEditingControl method.
public void ApplyCellStyleToEditingControl(
DataGridViewCellStyle dataGridViewCellStyle)
{
this.Font = dataGridViewCellStyle.Font;
}
//Implements the IDataGridViewEditingControl.EditingControlRowIndex 
//property.
public int EditingControlRowIndex
{
get
{
return rowIndex;
}
set
{
rowIndex = value;
}
}
//Implements the IDataGridViewEditingControl.EditingControlWantsInputKey 
//method.
public bool EditingControlWantsInputKey(
Keys key, bool dataGridViewWantsInputKey)
{
//Let the DateTimePicker handle the keys listed.
//switch (key & Keys.KeyCode)
//{
//   case Keys.Left:
//   case Keys.Up:
//   case Keys.Down:
//   case Keys.Right:
//   case Keys.Home:
//   case Keys.End:
//   case Keys.PageDown:
//   case Keys.PageUp:
//       return true;
//   default:
//       return !dataGridViewWantsInputKey;
//}
return DroppedDown;
}
//Implements the IDataGridViewEditingControl.PrepareEditingControlForEdit 
//method.
public void PrepareEditingControlForEdit(bool selectAll)
{
//No preparation needs to be done.
}
//Implements the IDataGridViewEditingControl
//.RepositionEditingControlOnValueChange property.
public bool RepositionEditingControlOnValueChange
{
get
{
return false;
}
}
//Implements the IDataGridViewEditingControl
//.EditingControlDataGridView property.
public DataGridView EditingControlDataGridView
{
get
{
return dataGridView;
}
set
{
dataGridView = value;
}
}
//Implements the IDataGridViewEditingControl
//.EditingControlValueChanged property.
public bool EditingControlValueChanged
{
get
{
return valueChanged;
}
set
{
valueChanged = value;
}
}
//Implements the IDataGridViewEditingControl
//.EditingPanelCursor property.
public Cursor EditingPanelCursor
{
get
{
return base.Cursor;
}
}
protected override void OnSelectedItemChanged(EventArgs e)
{
if (Loading) return;
//Notify the DataGridView that the contents of the cell
//have changed.
valueChanged = true;
this.EditingControlDataGridView.NotifyCurrentCellDirty(true);
base.OnSelectedItemChanged(e);
}
protected override void OnSelectedIndexChanged(EventArgs e)
{
if (Loading || DroppedDown) return;
//Notify the DataGridView that the contents of the cell
//have changed.
valueChanged = true;
this.EditingControlDataGridView.NotifyCurrentCellDirty(true);
base.OnSelectedIndexChanged(e);
SendKeys.Send("{ENTER}");
}
protected override void OnTextChanged(EventArgs e)
{
if (Loading) return;
valueChanged = true;
this.EditingControlDataGridView.NotifyCurrentCellDirty(true);
base.OnTextChanged(e);
}
protected override void OnDropDownClosed(EventArgs e)
{
if (originalIndex != SelectedIndex)
{
valueChanged = true;
this.EditingControlDataGridView.NotifyCurrentCellDirty(true);
}
base.OnDropDownClosed(e);
}
protected override void OnDropDown(EventArgs e)
{
//set dropdown width to accomodate items
var g = CreateGraphics();      
DropDownWidth = 
Items.Cast<string>().Max(s => 
{
var size = g.MeasureString(s, Font);
return size.Width.To<int>() + 30;
});
base.OnDropDown(e);
}
protected override void OnEnter(EventArgs e)
{
base.OnEnter(e);
DroppedDown = true;
}
}
}

Voici un exemple d'usage

var dc = new DropTextBoxColumn();
dc.Name = "FieldName";
dc.DataPropertyName = "FieldName";
dc.DropDownStyle = ComboBoxStyle.DropDownList;
var items = dc.Items = new string[]{ "one", "two", "three" };
items.Insert(0, "<None>");
dc.Items = items;
DirectGrid.Columns.Insert(1,dc);