borrowinfo.cs

一个基于.NETFramework架构的图书管理系统

using System;
using System.Collections.Generic;
using System.Text;
using System.Data;
using System.Data.SqlClient;

namespace DataAccess
{
    public class BorrowInfo
    {
        private SqlCommand cmd;
        public BorrowInfo()
        {
            cmd = new SqlCommand();
            cmd.CommandType = CommandType.StoredProcedure;
        }
        public DataSet GetBorrowInfoByBookNO(string bookno)
        {
            if (bookno == null)
                throw new ArgumentNullException("bookno");
            cmd.Parameters.Clear();
            cmd.CommandText = "GetBorrowInfoByBookNo";
            cmd.Parameters.Add("@BookNo", SqlDbType.Char, 15).Value = bookno;
            DataSet ds = DBAccess.QueryData(cmd);
            return ds;

        }
        public DataSet GetBorrowInfoByUserNO(string userno)
        {
            if (userno == null)
                throw new ArgumentNullException("userno");
            cmd.Parameters.Clear();
            cmd.CommandText = "GetBorrowInfoByUserNo";
            cmd.Parameters.Add("@UserNo", SqlDbType.Char, 15).Value = userno;
            DataSet ds = DBAccess.QueryData(cmd);
            return ds;
        }
        private bool HasBook(string bookno)
        {
            if (bookno == null)
                throw new ArgumentNullException("bookno");
            cmd.Parameters.Clear();
            cmd.CommandText = "HasThisBook";
            cmd.Parameters.Add("@BookNo", SqlDbType.Char, 15).Value = bookno;
            object o = DBAccess.GetScalar(cmd);
            if (o == null)
            {
                return false;
            }
            else
            {
                if ((int)o > 0)
                {
                    return true;
                }
                else
                {
                    return false;
                }
            }
        }
        private bool IsBorrowed(string bookno)
        {
            if (bookno == null)
                throw new ArgumentNullException("bookno");
            if (!HasBook(bookno))
                throw new NoRecordException("没有这本书");

            cmd.Parameters.Clear();
            cmd.CommandText = "IsBorrowed";
            cmd.Parameters.Add("@BookNO", SqlDbType.Char, 15).Value = bookno;
            object o = DBAccess.GetScalar(cmd);
            if (o == null)
            {
                return false;//没有借过
            }

            else
            {
                if (Convert.ToInt32 (o)>0)
                {
                    return false;//isreturned为1,已归还
                }
                else
                {
                    return true;//isreturned为0,未归还
                }
            }

        }
        public bool BorrowBook(string bookno, string userno)
        {
            if (bookno == null)
                throw new ArgumentNullException("bookno");
            if (userno == null)
                throw new ArgumentNullException("userno");
            if (IsBorrowed(bookno))
                return false;
            cmd.Parameters.Clear();
            cmd.CommandText = "BorrowBook";
            cmd.Parameters.Add("@BookNO", SqlDbType.Char, 15).Value = bookno;
            cmd.Parameters .Add ("@UserNo",SqlDbType .Char ,11).Value =userno ;
            try
            {
                DBAccess.ExecuteSQL(cmd);
                return true;
            }
            catch
            {
                return false;
            }
        }
        public bool ReturnBook(string bookno)
        {
            if (bookno == null)
            {
                throw new ArgumentNullException("bookno");
            }
            cmd.Parameters.Clear();
            cmd.CommandText = "ReturnBook";
            cmd.Parameters.Add("@BookNO", SqlDbType.Char, 15).Value = bookno;
            try
            {
                DBAccess.ExecuteSQL(cmd);
                return true;
            }
            catch
            {
                return false;
            }

        }
        public bool ReBorrow(string bookno)
        {
            if (bookno == null)
            {
                throw new ArgumentNullException("bookno");
            }
            cmd.Parameters.Clear();
            cmd.CommandText = "ReborrowBook";
            cmd.Parameters.Add("@BookNO", SqlDbType.Char, 15).Value = bookno;
            try
            {
                DBAccess.ExecuteSQL(cmd);
                return true;
            }
            catch
            {
                return false;
            }
        }

    }
}