2018-D

2018-D

新建数据库 test0317，目录为考试目录，并在完成建表后备份

1、建表：

use [test0317];

create table [STD_INFO](
	[std_id] int not null primary key,
	[std_name] varchar(20) not null,
	[std_sex] varchar(2) not null check([std_sex]='男' or [std_sex]='女')
);

create table [COURSE_INFO](
	[course_id] varchar(10) not null primary key,
	[course_name] varchar(20) not null,
)

create table [SCORES](
	[std_id] int references [STD_INFO]([std_id]),
	[course_id] varchar(10) references [COURSE_INFO]([course_id]),
	[score] int not null check([score]>=0 and [score]<=100)
)

insert into [STD_INFO] values(201833,'王二','男');
insert into [STD_INFO] values(201824,'张三','女');
update [STD_INFO] set std_id=201834 where std_name='张三';

insert into [COURSE_INFO] values('001','操作系统');
insert into [COURSE_INFO] values('002','嵌入式系统');

insert into [SCORES] values(201833,'001',70);
insert into [SCORES] values(201834,'001',90);
insert into [SCORES] values(201834,'002',20);

select * from [STD_INFO];
select * from [COURSE_INFO];
select * from [SCORES];

--根据姓名查询成绩
select [STD_INFO].[std_name] from [STD_INFO];
select [COURSE_INFO].[course_name],[SCORES].[score] from [STD_INFO],[COURSE_INFO],[SCORES] where [STD_INFO].[std_name]='张三' and [STD_INFO].[std_id]=[SCORES].[std_id] and [COURSE_INFO].[course_id]=[SCORES].[course_id];

--根据课程名查询成绩
select [COURSE_INFO].[course_name] from [COURSE_INFO];
select [STD_INFO].[std_id],[STD_INFO].[std_name],[SCORES].[score] from [STD_INFO],[COURSE_INFO],[SCORES] where [COURSE_INFO].[course_name]='操作系统' and [COURSE_INFO].[course_id]=[SCORES].[course_id] and [SCORES].[std_id]=[STD_INFO].[std_id];

2、解决方案：

解决方案结构：

Form1.cs[设计]

Form1 属性：

​ MaximizeBox = False

​ MinimizeBox = False

​ Text = 2018机试

​ 事件：

​ Load = Form1_Load

listView1 属性：

​ FullRowSelect = True

​ GridLine = True

​ View = Details

​ MultiSelect = False

comboBox1 / comboBox2 属性：

​ DropDownStyle = DropDownList

button1 / button2 事件：button1_Click / button2_Click

DB.cs:

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

namespace test0317
{
    internal class DB : IDisposable
    {
        private SqlConnection sqlConnection;
        public DB()
        {
            sqlConnection = new SqlConnection(@"server=.;database=test0317;Trusted_Connection=SSPI");
            sqlConnection.Open();
        }

        public DataTable GetBySql(string sql)
        {
            DataTable dt = new DataTable();
            SqlDataAdapter sqlDataAdapter = new SqlDataAdapter(new SqlCommand(sql,sqlConnection));
            sqlDataAdapter.Fill(dt);
            return dt;
        }

        public void Dispose()
        {
            sqlConnection.Close();
        }
    }
}

Form1.cs

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

namespace test0317
{
    public partial class Form1 : Form
    {
        DB db;
        public Form1()
        {
            InitializeComponent();
            db= new DB();
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            DataTable dt = db.GetBySql(@"select [STD_INFO].[std_name] from [STD_INFO];");
            for(int i=0; i<dt.Rows.Count; i++)
            {
                for(int j=0;j<dt.Columns.Count; j++)
                {
                    comboBox1.Items.Add(dt.Rows[i][j].ToString());
                }
            }
            comboBox1.SelectedIndex = 0;

            dt = db.GetBySql(@"select [COURSE_INFO].[course_name] from [COURSE_INFO];");
            for (int i = 0; i < dt.Rows.Count; i++)
            {
                for (int j = 0; j < dt.Columns.Count; j++)
                {
                    comboBox2.Items.Add(dt.Rows[i][j].ToString());
                }
            }
            comboBox2.SelectedIndex = 0;
        }

        private void button1_Click(object sender, EventArgs e)
        {
            listView1.Clear();
            listView1.Columns.Add("课程名", listView1.Width / 2 - 1, HorizontalAlignment.Left);
            listView1.Columns.Add("成绩", listView1.Width / 2 - 1, HorizontalAlignment.Left);
            DataTable dt = db.GetBySql(@"select [COURSE_INFO].[course_name],[SCORES].[score] from [STD_INFO],[COURSE_INFO],[SCORES] where [STD_INFO].[std_name]='"+comboBox1.Text+"'and [STD_INFO].[std_id]=[SCORES].[std_id] and [COURSE_INFO].[course_id]=[SCORES].[course_id]");
            listView1.BeginUpdate();
            for(int i=0; i < dt.Rows.Count; i++)
            {
                ListViewItem listViewItem = new ListViewItem();
                for(int j=0; j < dt.Columns.Count;j++)
                {
                    if (j <= 0)
                    {
                        listViewItem.Text = dt.Rows[i][j].ToString();
                    }
                    else
                    {
                        listViewItem.SubItems.Add(dt.Rows[i][j].ToString());
                    }
                }
                listView1.Items.Add(listViewItem);
            }
            listView1.EndUpdate();
        }

        private void button2_Click(object sender, EventArgs e)
        {
            listView1.Clear();
            listView1.Columns.Add("学号", listView1.Width / 3 - 1, HorizontalAlignment.Left);
            listView1.Columns.Add("学生名", listView1.Width / 3 - 1, HorizontalAlignment.Left);
            listView1.Columns.Add("成绩", listView1.Width / 3 - 1, HorizontalAlignment.Left);
            DataTable dt = db.GetBySql(@"select [STD_INFO].[std_id],[STD_INFO].[std_name],[SCORES].[score] from [STD_INFO],[COURSE_INFO],[SCORES] where [COURSE_INFO].[course_name]='" + comboBox2.Text + "' and [COURSE_INFO].[course_id]=[SCORES].[course_id] and [SCORES].[std_id]=[STD_INFO].[std_id];");
            listView1.BeginUpdate();
            for (int i = 0; i < dt.Rows.Count; i++)
            {
                ListViewItem listViewItem = new ListViewItem();
                for (int j = 0; j < dt.Columns.Count; j++)
                {
                    if (j <= 0)
                    {
                        listViewItem.Text = dt.Rows[i][j].ToString();
                    }
                    else
                    {
                        listViewItem.SubItems.Add(dt.Rows[i][j].ToString());
                    }
                }
                listView1.Items.Add(listViewItem);
            }
            listView1.EndUpdate();
        }
    }
}

3、结果：