Multi Column Combo Cell for the .NET 2.0 DataGridView Control

newColumn.DataPropertyName = Sds.Tables[0].Columns[0].ColumnName;<br />
            newColumn.DisplayMember = Sds.Tables[0].Columns[0].ColumnName;<br />
            newColumn.ValueMember = Sds.Tables[0].Columns[1].ColumnName;

if(currentRow!=null)
{
   // Here is the original source that I have omitted 
}
else
{
        string currentText = GetItemText(Items[e.Index]);

        //first redraw the normal while background
        SolidBrush normalBack = new SolidBrush(Color.White); //TODO: fix to be system edit box background
        e.Graphics.FillRectangle(normalBack, rec);


	if (DroppedDown && !(Margin.Top == rec.Top))
	{


		Type objectType = objCurrentItem.GetType();

		PropertyInfo propertyDisplay = objectType.GetProperty(this.DisplayMember);
		PropertyInfo propertyValue = objectType.GetProperty(this.ValueMember);

		PropertyInfo[] properties = new PropertyInfo[] { propertyValue, propertyDisplay };


		int currentOffset = rec.Left;

		SolidBrush HightlightedBack = new SolidBrush(System.Drawing.SystemColors.Highlight);
		if ((e.State & DrawItemState.Selected) == DrawItemState.Selected)
		{
			//draw selected color background
			e.Graphics.FillRectangle(HightlightedBack, rec);
		}

		bool addBorder = false;


		foreach (PropertyInfo p in properties)
		{
			string value = p.GetValue(objCurrentItem, null).ToString(); //TODO: support for different types!!!

			if (addBorder)
			{
				//draw dividing line
				//currentOffset ++; 
				SolidBrush gridBrush = new SolidBrush(Color.Gray); //TODO: make the border color configurable
				long linesNum = lineWidth;
				while (linesNum > 0)
				{
					linesNum--;
					Point first = new Point(rec.Left + currentOffset, rec.Top);
					Point last = new Point(rec.Left + currentOffset, rec.Bottom);
					e.Graphics.DrawLine(new Pen(gridBrush), first, last);
					currentOffset++;
				}
			}
			else
			{
				addBorder = true;
			}

			SizeF extent = e.Graphics.MeasureString(value, e.Font);
			decimal width = (decimal)extent.Width;
			//measure the string that we are goin to draw and cut it with wrapping if too large
			Rectangle textRec = new Rectangle(currentOffset, rec.Y, (int)decimal.Ceiling(width), rec.Height);

			//now draw the relevant to this column value text
			if ((e.State & DrawItemState.Selected) == DrawItemState.Selected)
			{
				//draw selected
				SolidBrush HightlightedText = new SolidBrush(System.Drawing.SystemColors.HighlightText);
				//now redraw the backgrond it order to wrap the previous field if was too large
				e.Graphics.FillRectangle(HightlightedBack, currentOffset, rec.Y, fixedAlignColumnSize, extent.Height);
				//draw text as is 
				e.Graphics.DrawString(value, e.Font, HightlightedText, textRec);
			}
			else
			{
				//now redraw the backgrond it order to wrap the previous field if was too large
				e.Graphics.FillRectangle(normalBack, currentOffset, rec.Y, fixedAlignColumnSize, extent.Height);
				//draw text as is 
				e.Graphics.DrawString(value, e.Font, NormalText, textRec);
			}
			//advance the offset to the next position
			currentOffset += fixedAlignColumnSize;
		}
	}
	else
	{
		//if happens when the combo is closed, draw single standard item view
		e.Graphics.DrawString(currentText, e.Font, NormalText, rec);
	}


}

protected override void OnDrawItem(System.Windows.Forms.DrawItemEventArgs e)<br />
{<br />
Rectangle rec = new Rectangle(e.Bounds.X, e.Bounds.Y, e.Bounds.Width, e.Bounds.Height);<br />
DataGridViewMultiColumnComboColumn column = ownerCell.OwningColumn as DataGridViewMultiColumnComboColumn;<br />
DataTable valuesTbl = column.valuesTbl;<br />
string joinByField = column.joinFieldName;<br />
SolidBrush NormalText = new SolidBrush(System.Drawing.SystemColors.ControlText);<br />
object currentItem = Items[e.Index];<br />
string currentText = GetItemText(currentItem);<br />
<br />
//If there is an item<br />
if (e.Index > -1)<br />
{<br />
//first redraw the normal while background<br />
SolidBrush normalBack = new SolidBrush(Color.White); //TODO: fix to be system edit box background<br />
e.Graphics.FillRectangle(normalBack, rec);<br />
if (DroppedDown && !(Margin.Top == rec.Top))<br />
{<br />
int currentOffset = rec.Left;<br />
<br />
//now find this text corrent join field<br />
DataRow[] itemRows = valuesTbl.Select("[" + joinByField + "]='" + currentText + "'");<br />
<br />
SolidBrush HightlightedBack = new SolidBrush(System.Drawing.SystemColors.Highlight);<br />
if ((e.State & DrawItemState.Selected) == DrawItemState.Selected)<br />
{<br />
//draw selected color background<br />
e.Graphics.FillRectangle(HightlightedBack, rec);<br />
}<br />
StreamWriter sw = new StreamWriter(File.OpenWrite("record"));<br />
foreach (DataRow currentRow in itemRows)<br />
{<br />
bool addBorder = false;<br />
<br />
foreach (object dataRowItem in currentRow.ItemArray)<br />
{<br />
string value = dataRowItem.ToString(); //TODO: support for different types!!!<br />
<br />
<br />
<br />
#region DrawLine<br />
if (addBorder)<br />
{<br />
//draw dividing line<br />
//currentOffset ++; <br />
SolidBrush gridBrush = new SolidBrush(Color.Gray); //TODO: make the border color configurable<br />
long linesNum = lineWidth;<br />
while (linesNum > 0)<br />
{<br />
linesNum--;<br />
Point first = new Point(rec.Left + currentOffset, rec.Top);<br />
Point last = new Point(rec.Left + currentOffset, rec.Bottom);<br />
e.Graphics.DrawLine(new Pen(gridBrush), first, last);<br />
currentOffset++;<br />
}<br />
//currentOffset++;<br />
}<br />
else<br />
addBorder = true;<br />
#endregion<br />
<br />
//measure the string that we are goin to draw and cut it with wrapping if too large<br />
SizeF extent = e.Graphics.MeasureString(value, e.Font);<br />
Rectangle textRec = new Rectangle(currentOffset, rec.Y, (int)extent.Width + 20, rec.Height);<br />
<br />
//now draw the relevant to this column value text<br />
if ((e.State & DrawItemState.Selected) == DrawItemState.Selected)<br />
{<br />
//draw selected<br />
SolidBrush HightlightedText = new SolidBrush(System.Drawing.SystemColors.HighlightText);<br />
//now redraw the backgrond it order to wrap the previous field if was too large<br />
e.Graphics.FillRectangle(HightlightedBack, currentOffset, rec.Y, fixedAlignColumnSize, extent.Height);<br />
//draw text as is <br />
e.Graphics.DrawString(value, e.Font, HightlightedText, textRec); sw.Write(value + "|");<br />
}<br />
else<br />
{<br />
//now redraw the backgrond it order to wrap the previous field if was too large<br />
e.Graphics.FillRectangle(normalBack, currentOffset, rec.Y, fixedAlignColumnSize, extent.Height);<br />
//draw text as is <br />
e.Graphics.DrawString(value, e.Font, NormalText, textRec); sw.Write(value + "|");<br />
}<br />
//advance the offset to the next position<br />
currentOffset += fixedAlignColumnSize;<br />
}<br />
sw.WriteLine();<br />
}<br />
sw.Close();<br />
}<br />
else<br />
//if happens when the combo is closed, draw single standard item view<br />
e.Graphics.DrawString(currentText, e.Font, NormalText, rec);<br />
}<br />
}<br />
/**************************************************************************************************/<br />
}