using System;
using System.Data;
using System.Data.SqlClient;
using System.Configuration;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;

public partial class _Default : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {

    }
    protected void BTQuery_Click(object sender, EventArgs e)
    {
        string connString;
        string bookID;
        bookID = TBbookID.Text;
        connString = "Initial Catalog=onlineBookstore;Data Source=(local);Integrated Security=SSPI;";
        SqlConnection Conn = new SqlConnection(connString);
        SqlCommand QueryCommand = new SqlCommand("select bookname,sellprice from bookinfo where bookID=@bookID ", Conn);
        SqlCommand QueryCommand1 = new SqlCommand("select sellprice from bookinfo where bookID=@bookID ", Conn);
      
        QueryCommand.Parameters.Add("@bookID", SqlDbType.VarChar, 25);
        QueryCommand.Parameters["@bookID"].Value = bookID;
        Conn.Open();        try

        {         
                string booknameValue = (string)QueryCommand.ExecuteScalar();
                TBbookname.Text = Convert.ToString(booknameValue);           
        }
        catch {
            TBbookname.Text = "没有此书";
        }
        try
        {          
                string sellpriceValue = (string)QueryCommand.ExecuteScalar();
                TBsellprice.Text = Convert.ToString(sellpriceValue);    
        }
        catch
        {
            TBsellprice.Text = "没有价格";
        }
        finally
        {
            Conn.Close();
        }
    }
}

sellprice 在数据库中是money型的，在这里显示不出来价格调试界面