Textbox Giving Me a Null Value??

DropDownList DDLItemCode = (DropDownList)e.Row.FindControl("DDLItemCode");
            TextBox ItemName = (TextBox)e.Row.FindControl("TBoxItemName");
 
            if (ItemName.Text != "")
            {
                string connection = dbconnection.Connection();
                SqlConnection con1 = new SqlConnection(connection);
                con1.Open();
 
                SqlCommand cmd1 = new SqlCommand("SELECT * FROM ITEMMAS WHERE CASH_ACC='" + ItemName.Text + "'", con1);
                SqlDataReader dr1 = cmd1.ExecuteReader();
  ...