DataGridView Find String

//Declare a List at Class level to hold the containing cells
//and an index to hold the current containing cell
List<datagridviewcell> containingCells = new List<datagridviewcell>();
int currentContainingCellListIndex = 0;
//In Event handler of Find button iterate all the rows and cells in 
//each row to find the cells containing the required text
//if found add that to the containingCells List   
ButtonFindText.Click += (sender, args) => {
    containingCells.Clear();
    currentContainingCellListIndex=0;
    foreach (DataGridViewRow row in dataGridView1.Rows)
    {
    	foreach (DataGridViewCell cell in row.Cells)
    	{
            if (cell.Value == DBNull.Value || cell.Value == null)
                continue;
            if (cell.Value.ToString().Contains(textToFind)) {
                containingCells.Add(cell);
            }
    	}	
    }
    if (containingCells.Count > 0)
    	dataGridView1.CurrentCell=
                containingCells[currentContainingCellListIndex++];
};
//In the Event handler of FindNext button set the next containingCell as
//the current cell of DataGridView
ButtonFindNext.Click += (sender, args) => {
    if (currentContainingCellListIndex < containingCells.Count ())
        dataGridView1.CurrentCell=
                containingCells[currentContainingCellListIndex++];
};

//Find using LINQ
FindUsingLinqButton.Click += (sender, args) => {
    currentContainingCellListIndex=0;
    containingCells = dataGridView1.Rows.OfType<DataGridViewRow>().SelectMany (
    	dgvr => dgvr.Cells.OfType<DataGridViewCell>().Where (dgvc => 
    		dgvc.Value != DBNull.Value && dgvc.Value != null &&
    		dgvc.Value.ToString().Contains(textToFind))).ToList();
//If query syntax is required
//containingCells = (from row in dataGridView1.Rows.OfType<DataGridViewRow>()
//      from cell in row.Cells.OfType<DataGridViewCell>()
//	  where cell.Value != DBNull.Value && cell.Value != null &&
//	        cell.Value.ToString().Contains("S")
//	  select cell).ToList();
    if (containingCells.Count > 0)
        	dataGridView1.CurrentCell=
                containingCells[currentContainingCellListIndex++];
    };
}