selectcourse.cs

学生管理（包括学生成绩 档案和课程） 学生可以录入数据

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Data.SqlClient;
using System.Drawing;
using System.Text;
using System.Windows.Forms;

namespace StudentManager
{
    public partial class SelectCourse : Form
    {
        private SqlConnection conn1 = null;
        private string selectstr = null;
        private SqlCommand Command11 = null;
        private SqlDataReader DataReader = null;
        private DataSet Dataset=new DataSet("SelectCourse");
        private SqlDataAdapter DataAdapter = null;
        private DataRow newrow = null;
        public SelectCourse()
        {
            InitializeComponent();
            conn1 = new SqlConnection(DataLevel.Connection.ConnString);
            selectstr = "Select Department from SelectCourse";
            Command11 = new SqlCommand();
            Command11.CommandText = selectstr;
            Command11.Connection = conn1;
            
         
        }

        private void SelectCourse_Load(object sender, EventArgs e)
        {
            if (conn1.State == ConnectionState.Closed)
                this.conn1.Open();
            this.selectstr = "select DepartmentName from Department";
            this.Command11.CommandText = selectstr;
            this.DataReader = this.Command11.ExecuteReader();
            while (this.DataReader.Read())
            {
                this.comboBoxDepartment.Items.Add(this.DataReader["DepartmentName"].ToString());
            }
            this.DataReader.Close();

            selectstr = "Select SemesterName from Semester";
            this.Command11.CommandText = selectstr;
            this.DataReader = this.Command11.ExecuteReader();
            while (this.DataReader.Read())
            {
                this.comboBoxSemester.Items.Add(this.DataReader["SemesterName"].ToString());
            }
            this.DataReader.Close();

            this.selectstr = "Select CourseName from Course";
            this.Command11.CommandText = selectstr;
            this.DataReader = this.Command11.ExecuteReader();
            while (DataReader.Read())
            {
                listBoxAll.Items.Add(this.DataReader["CourseName"].ToString());
            }
            this.DataReader.Close();
            this.conn1.Close();
            this.btnAdd.Enabled = false;
            this.btnDel.Enabled = false;
            this.btnOk.Enabled = false;
        }

        private void comboBoxDepartment_SelectedIndexChanged(object sender, EventArgs e)
        {
            this.conn1.Open();
            this.comboBoxClass.Items.Clear();
            this.listBoxHave.Items.Clear();
            this.comboBoxClass.Text = "";
            this.selectstr = "select ClassName from Class where DepartmentName=" + "'" + this.comboBoxDepartment.Text + "'";
            this.Command11.CommandText = this.selectstr;
            this.DataReader = this.Command11.ExecuteReader();
            while (this.DataReader.Read())
            {
                this.comboBoxClass.Items.Add(this.DataReader["ClassName"].ToString());
            }
            this.DataReader.Close();
            this.conn1.Close();
        }

        private void btnApply_Click(object sender, EventArgs e)
        {
            if (this.comboBoxClass.Text == "" | comboBoxDepartment.Text == "" | comboBoxSemester.Text == "")
            {
                MessageBox.Show("学院 班级 和 学期代码不能为空 ！否则不能成功选课 ！");
                return;
            }
            Listbox_fill();
            this.btnAdd.Enabled = true;
            this.btnDel.Enabled = true;
            this.btnOk.Enabled = true;

        }
        private void Listbox_fill()
        {
            if(conn1.State==ConnectionState.Closed)
                    this.conn1.Open();
            selectstr = "Select Course from SelectCourse where Department = '" + this.comboBoxDepartment.Text + "'and Class= '" +
                 this.comboBoxClass.Text + "'and Semester = '" + this.comboBoxSemester.Text + "'";
           
            this.Command11.CommandText = selectstr;
            this.DataReader = this.Command11.ExecuteReader();
            while (this.DataReader.Read())
            {
                listBoxHave.Items.Add(this.DataReader["Course"].ToString());
            }
            this.DataReader.Close();
            MessageBox.Show(this.comboBoxDepartment.Text+"学院   "+this.comboBoxClass.Text+"班级  "+"现在开始 \""+this.comboBoxSemester.Text+"\"  选课 ！");
        }
        private void btnExit_Click(object sender, EventArgs e)
        {
            this.Close();
        }

        private void btnAdd_Click(object sender, EventArgs e)
        {
            if (this.listBoxAll.Items.Count == 0)
            {
                MessageBox.Show("目前还没有预选的课 ！");
                return;
            }
            else
            {
                for (int i = 0; i < listBoxHave.Items.Count; i++)
                {
                    if (listBoxAll.SelectedItem.Equals(this.listBoxHave.Items[i]))
                    {
                        MessageBox.Show("此课程已选 ，请从新选过！");
                        return;
                    }
                }
                this.DataReader.Close();
               // this.selectstr = "select ClassName from Class where DepartmentName=" + "'" + this.comboBoxDepartment.Text + "'";
                selectstr = "Select * from SelectCourse where Department = '" + this.comboBoxDepartment.Text + "'and Class= '" +
                this.comboBoxClass.Text + "'and Semester = '" + this.comboBoxSemester.Text + "'";
                this.DataAdapter = new SqlDataAdapter(selectstr, this.conn1);
            //    this.Dataset.Clear();
                this.DataAdapter.Fill(this.Dataset, "SelectCourse");
                SqlCommandBuilder commadbuider = new SqlCommandBuilder(this.DataAdapter);
                newrow = Dataset.Tables[0].NewRow();
                newrow["Department"] = this.comboBoxDepartment.Text;
                newrow["Class"] = this.comboBoxClass.Text;
                newrow["Semester"] = this.comboBoxSemester.Text;
                newrow["Course"] = this.listBoxAll.SelectedItem.ToString();
                this.Dataset.Tables[0].Rows.Add(newrow);
                this.listBoxHave.Items.Add(this.listBoxAll.SelectedItem);
                MessageBox.Show("课程添加成功！");
                this.conn1.Close();
                
                
            }
        }

        private void btnOk_Click(object sender, EventArgs e)
        {
            if (conn1.State == ConnectionState.Closed)
            {
                this.conn1.Open();
            }
            SqlCommandBuilder commandbuiter = new SqlCommandBuilder(this.DataAdapter);
            this.DataAdapter.Update(this.Dataset, "SelectCourse");
            this.Dataset.AcceptChanges();
            this.conn1.Close();
        }

        private void btnDel_Click(object sender, EventArgs e)
        {
            for (int i = 0; i < this.Dataset.Tables[0].Rows.Count; i++)
            {
                if (this.Dataset.Tables[0].Rows[i]["Course"].ToString() == this.listBoxHave.SelectedItem.ToString())
                {
                    this.Dataset.Tables[0].Rows[i].Delete();
                    this.listBoxHave.Items.RemoveAt(this.listBoxHave.SelectedIndex);
                    MessageBox.Show("删除成功！");
                    return;
                }
            }
        }


    }
}