courses.cs

大二做的课程设计。一个学生信息管理系统

using System;
using System.Collections.Generic;
using System.Text;
using System.Data;
namespace StudentLibrary.Business
{
    using StudentLibrary.DataAccess;
    public class Courses
    {
        private DataBaseOperate cDbObject = null;
        private bool bConn = false;


        public Courses()
        {
            cDbObject = new DataBaseOperate();
            bConn = false;
        }

        public Courses(DataBaseOperate dbOperate)
        {
            cDbObject = dbOperate;
            bConn = true;
        }
        /// <summary>
        /// 功能：更新课程
        /// 由frmUpdateCourse窗体的btnSubmit_Click()方法调用
        /// </summary>
        /// <param name="iCourseId">课程号</param>
        /// <param name="dBeginDate">开课日期</param>
        /// <param name="dFinishDate">结课日期</param>
        /// <param name="sRemark">备注</param>
        /// <returns>更新成功返回true</returns>
        public bool UpdateCourse(
            int iCourseId,
            DateTime dBeginDate,
            DateTime dFinishDate,
            string sRemark)
        {
            string sSql =
                "update Course set"
                + " BeginDate = '" + dBeginDate.ToString() + "'"
                + ",FinishDate = '" + dFinishDate.ToString() + "'"
                + ",Remark = '" + sRemark + "'"
                + " where CourseId = " + iCourseId.ToString();

            try
            {
                cDbObject.Execute(sSql);
            }
            catch (Exception e)
            {
                throw (e);
            }
            return true;


        }
        /// <summary>
        /// 功能：查询科目
        /// 由frmUpdateCourse窗体加载时的getCourseInfo()方法调用
        /// </summary>
        /// <param name="iCourseId">科目ID</param>
        /// <param name="iClassId">班级ID</param>
        /// <param name="iSubjectId">课程ID</param>
        /// <returns>成功返回该班科目数据集</returns>
        public DataSet SelectCourse(
            int iCourseId,
            int iClassId,
            int iSubjectId)
        {
            string sSql =
                "select a.*"
                + ",b.ClassName"
                + ",c.SubjectName"
                + " from Course a"
                + ",Class b"
                + ",Subject c"
                + " where a.ClassId = b.ClassId"
                + " and a.SubjectId = c.SubjectId";

            if (iCourseId != -1)
            {
                sSql += " and a.CourseId = " + iCourseId.ToString();
            }
            if (iClassId != -1)
            {
                sSql += " and a.ClassId = " + iClassId.ToString();
            }
            if (iSubjectId != -1)
            {
                sSql += " and a.SubjectId = " + iSubjectId.ToString();
            }

            DataSet dataSet = new DataSet();
            try
            {
                dataSet = cDbObject.Search(sSql, "Course");
            }
            catch (Exception e)
            {
                throw (e);
            }
            return dataSet;
        }
        /// <summary>
        ///功能： 为一个班级建立一门新的课程
        /// 由frmNewCourse窗体的btnCreat_Click()方法调用
        /// </summary>
        /// <param name="iClassId">班级ID</param>
        /// <param name="iSubjectId">科目ID</param>
        /// <param name="dBeginDate">开课日期</param>
        /// <param name="dFinishDate">结课日期</param>
        /// <param name="sRemark">备注</param>
        /// <returns>成功建立返回true</returns>
        public bool InsertCourse(
            int iClassId,
            int iSubjectId,
            DateTime dBeginDate,
            DateTime dFinishDate,
            string sRemark)
        {
            string sSql =
                "insert Course("
                + "ClassId"
                + ",SubjectId"
                + ",BeginDate"
                + ",FinishDate"
                + ",Remark"
                + ")"
                + "values("
                + iClassId.ToString()
                + "," + iSubjectId.ToString()
                + ",'" + dBeginDate.ToString() + "'"
                + ",'" + dFinishDate.ToString() + "'"
                + ",'" + sRemark + "'"
                + ")";

            try
            {
                cDbObject.Execute(sSql);
            }
            catch (Exception e)
            {
                throw (e);
            }
            return true;
        }
        /// <summary>
        /// 功能：删除改班的课程
        /// 由frmUpdateCourse窗体的btnDelete_Click()方法调用
        /// </summary>
        /// <param name="iCourseId">课程ID</param>
        /// <param name="iSubjectId">科目ID</param>
        /// <param name="iClassId">班级ID</param>
        /// <returns>成功返回true</returns>
        public bool DeleteCourse(
            int iCourseId,
            int iSubjectId,
            int iClassId)
        {
            string sSql =
                "delete Course"
                + " where 1 = 1";
            if (iCourseId != -1)
            {
                sSql += " and CourseId = " + iCourseId.ToString();
            }
            if (iSubjectId != -1)
            {
                sSql += " and SubjectId = " + iSubjectId.ToString();
            }
            if (iClassId != -1)
            {
                sSql += " and ClassId = " + iClassId.ToString();
            }
            try
            {
                cDbObject.Execute(sSql);
            }
            catch (Exception e)
            {
                throw (e);
            }
            return true;
        }
        public void Dispose()
        {
            Dispose(true);
            GC.SuppressFinalize(true);
        }
        /// <summary>
        /// 关闭数据库
        /// </summary>
        /// <param name="disposing"></param>
        public virtual void Dispose(bool disposing)
        {
            if (!disposing)
            {
                return;
            }

            if (!bConn)
            {
                cDbObject.CloseDataBase();
            }
        }
    }
}