Problems with DataBinding not updating

[Evan]

I have a textbox bound to a column in a DataTable using DataBinding. I have a
Next button and in the Click Event it moves the current position of the
CurrencyManager to the next position. The CurrencyManager is moving to the
next position but the textbox is not being updated with the value of the next
row, it stays at the value of the first row.

// Initialization
string stockItemSelect = "SELECT stock_number "FROM po_stock_item ";
m_daStockItem = new NpgsqlDataAdapter(stockItemSelect, m_posDBConn);
...
m_daStockItem.Fill(m_dsLineItem, "stock_item");
....
tb_item.DataBindings.Add("Text", m_dsLineItem.Tables["stock_item"],
"stock_number");

// Code in Click event of Next button
CurrencyManager cmItem = (CurrencyManager)this.BindingContext[m_dsLineItem,
"stock_item"];
if (cmItem.Position < cmItem.Count - 1)
cmItem.Position++;
Evan