Search on key up

public void SearchOnKeyUp(string strTableName
, string strIDColumnName
, string strCodeColumnName
, string strNameColumnName
, TextBox txtCode
, TextBox txtName
, KeyEventArgs e)
{
string sTypedText = "";
string sFoundText = "";
string sAppendText = "";
string strSQL = "";
DBUtilities db = new DBUtilities();
DataSet ds = null;

switch (e.KeyCode)
{
case Keys.Back:
break;
case Keys.Left:
break;
case Keys.Right:
break;
case Keys.Tab:
break;
case Keys.Up:
break;
case Keys.Delete:
break;
case Keys.Down:
break;
default:
sTypedText = txtCode.Text;
strSQL = "SELECT TOP 1 " + strIDColumnName +
", " + strCodeColumnName +
", " + strNameColumnName +
" FROM " + strTableName +
" WHERE " + strCodeColumnName + " LIKE " + db.CDBStr(sTypedText + "%");
ds = db.GetSQLDataSet(strSQL);
if (ds.Tables[0].Rows.Count > 0)
{
sFoundText = ds.Tables[0].Rows[0][strCodeColumnName].ToString();
sAppendText = sFoundText.Substring(sTypedText.Length);
txtCode.Tag = ds.Tables[0].Rows[0][strIDColumnName].ToString();
txtCode.Text = sFoundText;
txtName.Text = ds.Tables[0].Rows[0][strNameColumnName].ToString();

txtCode.SelectionStart = sTypedText.Length;
txtCode.SelectionLength = sAppendText.Length;
}
break;
}
ds = null;
db = null;
}