C#

Private Sub DataGridView1_CellClick(ByVal sender As Object, ByVal e As System.Windows.Forms.DataGridViewCellEventArgs) Handles DataGridview1.CellClick
    If DataGridview1.CurrentCell.OwningColumn.Name = "TransDate" Then
        Dim objPoint As Point

        'Getting the exact location of the cell with respect to Form1.
        'Note- Me.Location is added here alongwith DataGridView1.Location and
        'DataGridView1.GetDisplayRectangle().Location.
        'This is done because the form frmDate we are calling is external to Form1 and if we don't add
        'Me.Location
        'here, frmDate won't open exactly at the desired point if we move or resize Form1. Instead of
        'frmDate if we use any control inside Form1 to place over 'TransDate' column then remove
        'Me.Location here and the next two lines.
        objPoint = (Me.Location + DataGridview1.Location + DataGridview1.GetCellDisplayRectangle(8,
        DataGridview1.CurrentCellAddress.Y, True).Location)

        'Setting the exact location where frmDate will be opened. The last digits may vary according to
        'your requirement.
        objPoint.X = objPoint.X - 158
        objPoint.Y = objPoint.Y + 28
            
        objFrmDate = New frmDate()
        objFrmDate.Location = objPoint
        objFrmDate.ShowDialog(Me)
        objFrmDate = Nothing
    End If
End Sub

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Drawing;
using System.Windows.Forms;

namespace MyNamespace
{
    public class ControlUtilityClass
    {
        /// 
        /// Use this static method like this,
        /// DataGridView datagridview = (DataGridView)sender;//sender is a parameter from the event handler that rise from DataGridView Control.
        /// DataGridViewCell cell = datagridview.CurrentCell;
        /// Rectangle bounds = MyNamespace.ControlUtilityClass.Get_DataGridCellLocationAndSize(cell);
        /// this.dateTimePicker1.Bounds = bounds;
        /// 
        /// 
        /// 
        public static Rectangle Get_DataGridCellLocationAndSize(DataGridViewCell cell)
        {
            Rectangle result;
            Rectangle rec = cell.DataGridView.GetCellDisplayRectangle(cell.ColumnIndex,
                    cell.RowIndex, false);
            Rectangle rec1 = cell.DataGridView.RectangleToScreen(rec);
            result = cell.DataGridView.FindForm().RectangleToClient(rec1);
            return result;
        }
    }
}

dim objFrmSubForm as New frmSubForm()
	objFrmSubForm.Dock=DockStyle.Fill
	objFrmSubForm.Show()
	objFrmSubForm=Nothing