C#学生信息管理系统-代码展示
编程环境：SQL Server 2019
Visual Studio 2019
(仅功能代码)
- 登陆
private void button2_Click(object sender, EventArgs e) //登陆
{
string username = textBoxUserName.Text.Trim(); //取出账号
string password = EncryptWithMD5(textBoxPassWord.Text.Trim()); //取出密码
name = username;
//string connstr = ConfigurationManager.ConnectionStrings["connectionString"].ToString(); //读取连接字符串
string myConnString = "Data Source=.;Initial Catalog=Text;Persist Security Info=True;User ID=sa;Password=110023"; //连接字符串 Data source为服务器的名字 Text为连接的库
SqlConnection sqlConnection = new SqlConnection(myConnString); //实例化连接对象
sqlConnection.Open();
string sql = "select UserID,UserPassword from UserMessage where UserID = '" + username + "' and UserPassword = '" + password + "'"; //编写SQL命令
SqlCommand sqlCommand = new SqlCommand(sql, sqlConnection);
SqlDataReader sqlDataReader = sqlCommand.ExecuteReader();
string select_by_id="select * from UserMessage where UserID='" + username+"'";
if (sqlDataReader.HasRows && radioButton1.Checked && txtVerifyCode.Text.Equals(VerifyCode, StringComparison.OrdinalIgnoreCase)) //学生成功登录
{
MessageBox.Show("欢迎使用！"); //登录成功
FormStudent formstudent = new FormStudent();
formstudent.Show();
//this.Hide();
}
if (sqlDataReader.HasRows && radioButton2.Checked && txtVerifyCode.Text.Equals(VerifyCode, StringComparison.OrdinalIgnoreCase)) //管理员成功登录
{
MessageBox.Show("欢迎使用！"); //登录成功
FormAdmini formAdmini = new FormAdmini();
formAdmini.Show();
// this.Hide();
}
if (textBoxUserName.Text.Trim() == "")
{
MessageBox.Show("请输入学号/工号！");
}
if (textBoxPassWord.Text.Trim() == "")
{
MessageBox.Show("请输入密码！");
}
//验证码
if (string.IsNullOrEmpty(txtVerifyCode.Text))
{
MessageBox.Show("请输入验证码！");
return;
}
if (sqlDataReader.HasRows )
{
//label1.Text = "Log in :" + username;
if (txtVerifyCode.Text.Equals(VerifyCode, StringComparison.OrdinalIgnoreCase))
{
label1.Text = "Log in :" + username;
}
else
{
MessageBox.Show("验证码错误!请重新输入！");
}
}
else if(!sqlDataReader.Read() && textBoxPassWord.Text.Trim() !="" && textBoxUserName.Text.Trim() != "")
{
MessageBox.Show("密码输入错误！", "notice", MessageBoxButtons.OK, MessageBoxIcon.Error);
}
sqlConnection.Close();
}
验证码
private string MakeCode(int codeLen)
{
if (codeLen < 1)
{
return string.Empty;
}
int number;
string checkCode = string.Empty;
Random random = new Random();
for (int index = 0; index < codeLen; index++)
{
number = random.Next();
if (number % 2 == 0)
{
checkCode += (char)('0' + (char)(number % 10)); //生成数字
}
else
{
checkCode += (char)('A' + (char)(number % 26)); //生成字母
}
}
return checkCode;
}
private Image CreateCodeImg(string checkCode)
{
if (string.IsNullOrEmpty(checkCode))
{
return null;
}
Bitmap image = new Bitmap((int)Math.Ceiling((checkCode.Length * 12.5)), 22);
Graphics graphic = Graphics.FromImage(image);
try
{
Random random = new Random();
graphic.Clear(Color.White);
int x1 = 0, y1 = 0, x2 = 0, y2 = 0;
for (int index = 0; index < 25; index++)
{
x1 = random.Next(image.Width);
x2 = random.Next(image.Width);
y1 = random.Next(image.Height);
y2 = random.Next(image.Height);
graphic.DrawLine(new Pen(Color.Silver), x1, y1, x2, y2);
}
Font font = new Font("Arial", 12, (FontStyle.Bold | FontStyle.Italic));
LinearGradientBrush brush = new LinearGradientBrush(new Rectangle(0, 0, image.Width, image.Height), Color.Red, Color.DarkRed, 1.2f, true);
graphic.DrawString(checkCode, font, brush, 2, 2);
int x = 0;
int y = 0;
//画图片的前景噪音点
for (int i = 0; i < 100; i++)
{
x = random.Next(image.Width);
y = random.Next(image.Height);
image.SetPixel(x, y, Color.FromArgb(random.Next()));
}
//画图片的边框线
graphic.DrawRectangle(new Pen(Color.Silver), 0, 0, image.Width - 1, image.Height - 1);
return image;
}
finally
{
graphic.Dispose();
}
}
private void pictureBox1_Click(object sender, EventArgs e)
{
VerifyCode = MakeCode(5);
pictureBox1.Image = CreateCodeImg(VerifyCode);
}
密码加密
public static string EncryptWithMD5(string source) //MD5加密
{
byte[] sor = Encoding.UTF8.GetBytes(source);
MD5 md5 = MD5.Create();
byte[] result = md5.ComputeHash(sor);
StringBuilder strbul = new StringBuilder(40);
for (int i = 0; i < result.Length; i++)
{
strbul.Append(result[i].ToString("x2"));//加密结果"x2"结果为32位,"x3"结果为48位,"x4"结果为64位
}
return strbul.ToString();
}
- 注册
private void buttonOK_Click(object sender, EventArgs e)//注册成功
{
try
{
string connString = "Data Source =.; Initial Catalog = Text; Persist Security Info = True;User ID = sa; Password =110023";//数据库连接字符串
SqlConnection connection = new SqlConnection(connString);//创建connection对象
string sql = "insert into UserMessage (UserName, UserID , UserPassword, UserIdentity ,UserSex, UserNumber ,UserBirthday ,UserPhoto ) " +
"values (@username, @userid, @userpassword,@useridentity,@usersex,@usernumber,@userbirthday,@userphoto)";
SqlCommand command = new SqlCommand(sql, connection);
SqlParameter sqlParameter = new SqlParameter("@userid", textBoxNum.Text);
command.Parameters.Add(sqlParameter);
sqlParameter = new SqlParameter("@username", textBoxName.Text);
command.Parameters.Add(sqlParameter);
sqlParameter = new SqlParameter("@userpassword", EncryptWithMD5(textBoxPassword.Text));
command.Parameters.Add(sqlParameter);
sqlParameter = new SqlParameter("@usersex", comboBoxsex.Text);
command.Parameters.Add(sqlParameter);
sqlParameter = new SqlParameter("@usernumber", textBoxNumber.Text);
command.Parameters.Add(sqlParameter);
sqlParameter = new SqlParameter("@userbirthday", dateTimePickerbirth.Value);
command.Parameters.Add(sqlParameter);
sqlParameter = new SqlParameter("@useridentity", comboBoxidentity.Text);
command.Parameters.Add(sqlParameter);
sqlParameter = new SqlParameter("@userphoto", SqlDbType.VarBinary, mybyte.Length, ParameterDirection.Input, false, 0, 0, null, DataRowVersion.Current, mybyte);
command.Parameters.Add(sqlParameter);
//打开数据库连接
connection.Open();
command.ExecuteNonQuery();
connection.Close();
MessageBox.Show("注册成功！");
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
this.Close();
}
密码加密
public static string EncryptWithMD5(string source)//MD5加密
{
byte[] sor = Encoding.UTF8.GetBytes(source);
MD5 md5 = MD5.Create();
byte[] result = md5.ComputeHash(sor);
StringBuilder strbul = new StringBuilder(40);
for (int i = 0; i < result.Length; i++)
{
strbul.Append(result[i].ToString("x2"));//加密结果"x2"结果为32位,"x3"结果为48位,"x4"结果为64位
}
return strbul.ToString();
}
对密码、学号和联系方式的限制
private void textBoxPassword_Leave(object sender, EventArgs e)//对密码的设置
{
if (textBoxPassword.Text.Trim() != "")
{
//使用regex（正则表达式）进行格式设置 至少有数字、大写字母各一个。最少3个字符、最长20个字符。
Regex regex = new Regex(@"(?=.*[0-9])(?=.*[A-Z]).{3,20}");
if (regex.IsMatch(textBoxPassword.Text))//判断格式是否符合要求
{
//MessageBox.Show("输入密码格式正确!");
}
else
{
MessageBox.Show("密码由至少一个大写字母、最少3个字符组成！");
textBoxPassword.Focus();
}
}
else
{
MessageBox.Show("密码不能为空！");
}
}
private void textBoxNum_Leave(object sender, EventArgs e)//对学号/工号的设置
{
if (textBoxNum.Text.Trim() != "")
{
//使用regex（正则表达式）进行格式设置 至少有数字最少7个字符、最长20个字符。
Regex regex = new Regex(@"(?=.*[0-9]).{7,20}");
if (regex.IsMatch(textBoxNum.Text))//判断格式是否符合要求
{
//MessageBox.Show("输入密码格式正确!");
}
else
{
MessageBox.Show("学号/工号至少为7个字符、最长20个字符！");
textBoxNum.Focus();
}
}
else
{
MessageBox.Show("用户名不能为空！");
}
}
private void textBoxNumber_Leave(object sender, EventArgs e)//联系方式设置
{
if (textBoxNumber.Text.Trim() != "")
{
//使用regex（正则表达式）进行格式设置 至少有数字最少7个字符、最长20个字符。
Regex regex = new Regex(@"(?=.*[0-9]).{7,20}");
if (regex.IsMatch(textBoxNumber.Text))//判断格式是否符合要求
{
//MessageBox.Show("输入联系方式格式正确!");
}
else
{
MessageBox.Show("联系方式至少有7个字符、最长20个字符！");
textBoxNumber.Focus();
}
}
else
{
//MessageBox.Show("联系方式不能为空！");
}
}
上传照片
private void buttonphoto_Click(object sender, EventArgs e)//上传照片
{
OpenFileDialog openFileDialog = new OpenFileDialog();
openFileDialog.ShowDialog();
string picturePath = openFileDialog.FileName;//获取图片路径
//创建FileStream对象
FileStream fs = new FileStream(picturePath, FileMode.Open, FileAccess.Read);
//声明Byte数组
mybyte = new byte[fs.Length];
//读取数据
fs.Read(mybyte, 0, mybyte.Length);
Image image = Image.FromStream(fs);
userphoto.Image = image;
fs.Close();
}
- 学生登陆
个人信息
public FormStudent()
{
InitializeComponent();
Form1 form1 = new Form1(); //将登陆窗体的账号传递到此窗体
label7.Text = form1.Get();
//取出图片
SqlConnection conn = new SqlConnection("Data Source=.;Initial Catalog=Text;User ID=sa;Password=110023");
conn.Open();
String select_by_id = "select UserPhoto from UserMessage where UserID='" + label7.Text + "'";
SqlCommand sqlCommand1 = new SqlCommand(select_by_id, conn);
DataSet dt = new DataSet();
SqlDataAdapter da = new SqlDataAdapter(select_by_id, conn);
da.Fill(dt,"UserMessage");
int c = dt.Tables["UserMessage"].Rows.Count;
if (c > 0)
{
Byte[] mybyte = new byte[0];
mybyte = (Byte[])(dt.Tables["UserMessage"].Rows[c - 1]["UserPhoto"]);
MemoryStream ms = new MemoryStream(mybyte);
pictureBox1.Image = Image.FromStream(ms);
}
else
pictureBox1.Image = null;
conn.Close();
}
private void 个人信息ToolStripMenuItem_Click(object sender, EventArgs e)
{
panel3.Show();
string StuSno = label7.Text.Trim();
String conn = "Data Source =.; Initial Catalog = Text; Persist Security Info = True;User ID = sa; Password = 110023";
SqlConnection sqlconnection = new SqlConnection(conn);//实例化连接对象
try
{
sqlconnection.Open();
String select_by_sno = "select * from Student where Sno='" + StuSno + "'";//数据库操作的代码
SqlCommand cmd = new SqlCommand(select_by_sno, sqlconnection);
SqlDataReader sqlDataReader = cmd.ExecuteReader();//返回读取到的数据
BindingSource bindingsource = new BindingSource();//封装窗体的数据源
bindingsource.DataSource = sqlDataReader; ;//将读到的数据传递给窗体的数据源
dataGridView1.DataSource = bindingsource;//再将数据源赋值给dataGridView
}
catch
{
MessageBox.Show("查询语句有误，请认真检查SQL语句");
}
finally
{
sqlconnection.Close();//关闭数据库连接
}
}
选课管理
private void 选课结果ToolStripMenuItem_Click(object sender, EventArgs e)
{
panel1.Show();
panel2.Hide();
panel3.Hide();
string StuSno = label7.Text.Trim();
String conn = "Data Source =.; Initial Catalog = Text; Persist Security Info = True;User ID = sa; Password = 110023";
SqlConnection sqlconnection = new SqlConnection(conn);//实例化连接对象
try
{
sqlconnection.Open();
String select_by_sno = "select * from SC where Sno='" + StuSno + "'";//数据库操作的代码
SqlCommand cmd = new SqlCommand(select_by_sno, sqlconnection);
SqlDataReader sqlDataReader = cmd.ExecuteReader();//返回读取到的数据
BindingSource bindingsource = new BindingSource();//封装窗体的数据源
bindingsource.DataSource = sqlDataReader; ;//将读到的数据传递给窗体的数据源
dataGridView2.DataSource = bindingsource;//再将数据源赋值给dataGridView
}
catch
{
MessageBox.Show("查询语句有误，请认真检查SQL语句");
}
finally
{
sqlconnection.Close();//关闭数据库连接
}
}
成绩查询
private void 成绩查询ToolStripMenuItem_Click(object sender, EventArgs e)
{
//panel1.Hide();
//panel2.Hide();
panel2.Show();
}
private void button1_Click(object sender, EventArgs e) //查询
{
string StuSno = label7.Text.Trim();
string StuCno = textBox1.Text.Trim();
String conn = "Data Source =.; Initial Catalog = Text; Persist Security Info = True;User ID = sa; Password = 110023";
SqlConnection sqlconnection = new SqlConnection(conn);//实例化连接对象
try
{
sqlconnection.Open();
String select_by_sno = "select * from SC where Sno='" + StuSno + "'and Cno ='" +StuCno+"'";//数据库操作的代码
SqlCommand cmd = new SqlCommand(select_by_sno, sqlconnection);
SqlDataReader sqlDataReader = cmd.ExecuteReader();//返回读取到的数据
BindingSource bindingsource = new BindingSource();//封装窗体的数据源
bindingsource.DataSource = sqlDataReader; ;//将读到的数据传递给窗体的数据源
dataGridView3.DataSource = bindingsource;//再将数据源赋值给dataGridView
}
catch
{
MessageBox.Show("查询语句有误，请认真检查SQL语句");
}
finally
{
sqlconnection.Close();//关闭数据库连接
}
}
- 管理员登陆
private void button1_Click_1(object sender, EventArgs e)//管理信息
{
StuInfor stuinfor = new StuInfor();
stuinfor.Show();
}
private void button2_Click(object sender, EventArgs e)//管理成绩
{
StuGrade stuGrade = new StuGrade();
stuGrade.Show();
}
private void button3_Click(object sender, EventArgs e)//管理课程
{
StuCourse stuCourse = new StuCourse();
stuCourse.Show();
}
学生信息管理
增加
SqlConnection con = new SqlConnection("Data Source=.;Initial Catalog=Text;Persist Security Info=True;User ID=sa;Password=110023");
private void buttonAdd_Click(object sender, EventArgs e)//增加
{
string StuSno = textBoxsno.Text.Trim();
string StuSname = textBoxsname.Text.Trim();
string StuSsex = textBoxsex.Text.Trim();
string StuSage = textBoxsage.Text.Trim();
string StuSdept = textBoxsdept.Text.Trim();
//SqlConnection con = new SqlConnection("Data Source =.; Initial Catalog = Text; Persist Security Info = True;User ID = sa; Password = 110023"); //连接数据库
try
{
con.Open(); //打开数据库
string insertStr = "INSERT INTO Student(Sno,Sname,Ssex,Sage,Sdept)" + "VALUES('" + StuSno + "','" + StuSname + "','" + StuSsex + "'," + StuSage + ",'" + StuSdept + "')";
SqlCommand cmd = new SqlCommand(insertStr, con);
cmd.ExecuteNonQuery(); //将增加后的信息直接显示出来
}
catch
{
MessageBox.Show("输入数据违法要求！");
}
finally
{
con.Close(); //关闭数据库
}
this.studentTableAdapter.Fill(this.textDataSet1.Student);
}
删除
private void buttonDelete_Click(object sender, EventArgs e)//删除
{
try
{
con.Open(); //打开数据库
string select_Sno = dataGridView1.SelectedRows[0].Cells[0].Value.ToString();//选择的当前行第一列的值，也就是Sno
string delete_by_Sno = "DELETE FROM Student WHERE Sno='" + select_Sno + "'";//sql删除语句
SqlCommand cmd = new SqlCommand(delete_by_Sno, con);
cmd.ExecuteNonQuery(); //将增加后的信息直接出来
}
catch
{
MessageBox.Show("请选择正确行！");
}
finally
{
con.Close(); //关闭数据库
}
this.studentTableAdapter.Fill(this.textDataSet1.Student);
}
在数据库中增加性别限制
ALTER TABLE Student ADD CONSTRAINT C1 CHECK(Ssex IN('男','女'));
删除
private void buttonDelete_Click(object sender, EventArgs e)//删除
{
try
{
con.Open(); //打开数据库
string select_Sno = dataGridView1.SelectedRows[0].Cells[0].Value.ToString();//选择的当前行第一列的值，也就是Sno
string delete_by_Sno = "DELETE FROM Student WHERE Sno='" + select_Sno + "'";//sql删除语句
SqlCommand cmd = new SqlCommand(delete_by_Sno, con);
cmd.ExecuteNonQuery(); //将增加后的信息直接出来
}
catch
{
MessageBox.Show("请选择正确行！");
}
finally
{
con.Close(); //关闭数据库
}
this.studentTableAdapter.Fill(this.textDataSet1.Student);
}
修改
private void buttonModify_Click(object sender, EventArgs e)//修改
{
string StuSno = textBoxsno.Text.Trim();
string StuSname = textBoxsname.Text.Trim();
string StuSsex = textBoxsex.Text.Trim();
string StuSage = textBoxsage.Text.Trim();
string StuSdept = textBoxsdept.Text.Trim();
try
{
string insertStr = "";
string insertStr1 = "";
string insertStr2 = "";
string insertStr3 = "";
con.Open();
if (StuSname != "")
{
insertStr = "UPDATE Student SET Sname = '" + StuSname + "' WHERE Sno = '" + StuSno + "'"; //修改名字
SqlCommand cmd = new SqlCommand(insertStr, con);
cmd.ExecuteNonQuery();
}
if (StuSsex != "")
{
insertStr1 = "UPDATE Student SET Ssex = '" + StuSsex + "' WHERE Sno = '" + StuSno + "'"; //修改性别
SqlCommand cmd1 = new SqlCommand(insertStr1, con);
cmd1.ExecuteNonQuery();
}
if (StuSdept != "")
{
insertStr2 = "UPDATE Student SET Sdept = '" + StuSdept + "' WHERE Sno = '" + StuSno + "'"; //修改专业
SqlCommand cmd2 = new SqlCommand(insertStr2, con);
cmd2.ExecuteNonQuery();
}
if (StuSage != "")
{
insertStr3 = "UPDATE Student SET Sage = '" + StuSage + "' WHERE Sno = '" + StuSno + "'"; //修改年龄
SqlCommand cmd3 = new SqlCommand(insertStr3, con);
cmd3.ExecuteNonQuery();
}
}
catch
{
MessageBox.Show("输入数据违反要求");
}
finally
{
con.Close(); //关闭数据库
}
this.studentTableAdapter.Fill(this.textDataSet1.Student);
}
查询
private void buttonSearch_Click(object sender, EventArgs e)//查询
{
string StuSno = textBoxsno.Text.Trim();
string StuSname = textBoxsname.Text.Trim();
string StuSsex = textBoxsex.Text.Trim();
string StuSage = textBoxsage.Text.Trim();
string StuSdept = textBoxsdept.Text.Trim();
String conn = "Data Source =.; Initial Catalog = Text; Persist Security Info = True;User ID = sa; Password = 110023";
SqlConnection sqlconnection = new SqlConnection(conn);//实例化连接对象
try
{
String select_by_id = "select * from Student where ";
int flag = 0;
sqlconnection.Open();
if (StuSno != "")
select_by_id += "Sno='" + StuSno + "'"; // 按学号查
if (StuSname != "")
{
if (flag == 0)
{
select_by_id += "Sname LIKE'" + StuSname + "'";
flag = 1;
}
if (flag == 1)
select_by_id += "And Sname LIKE'" + StuSname + "'";
}
if (StuSage != "")
{
if (flag == 0)
{
select_by_id += "Sage='" + StuSage + "'";
flag = 1;
}
if (flag == 1)
select_by_id += "And Sage='" + StuSage + "'";
}
if (StuSdept != "")
{
if (flag == 0)
{
select_by_id += "Sdept='" + StuSdept + "'";
flag = 1;
}
if (flag == 1)
select_by_id += "And Sdept='" + StuSdept + "'";
}
if (StuSsex != "")
{
if (flag == 0)
{
select_by_id += "Ssex='" + StuSsex + "'";
flag = 1;
}
if (flag == 1)
select_by_id += "And Ssex='" + StuSsex + "'";
}
SqlCommand sqlcommand = new SqlCommand(select_by_id, sqlconnection);
SqlDataReader sqldatareader = sqlcommand.ExecuteReader();
BindingSource bindingsource = new BindingSource();
bindingsource.DataSource = sqldatareader;
dataGridView1.DataSource = bindingsource;
}
catch
{
MessageBox.Show("查询语句有误，请认真检查SQL语句");
}
finally
{
sqlconnection.Close();
}
}
学生成绩管理
增加
private void buttonAdd_Click(object sender, EventArgs e)//增加
{
string StuSno = textBoxsno.Text.Trim();
string StuCno = textBoxcno.Text.Trim();
string StuGrade = textBoxgrade.Text.Trim();
try
{
con.Open(); //打开数据库
string insertStr = "INSERT INTO SC(Sno,Cno,Grade)" + "VALUES('" + StuSno + "','" + StuCno + "','" + StuGrade + "')";
SqlCommand cmd = new SqlCommand(insertStr, con);
cmd.ExecuteNonQuery(); //将增加后的信息直接显示出来
}
catch
{
MessageBox.Show("输入数据违法要求！");
}
finally
{
con.Close();
}
this.sCTableAdapter.Fill(this.textDataSet2.SC);
}
删除
private void buttonDelete_Click(object sender, EventArgs e)//删除
{
try
{
con.Open(); //打开
string select_id = dataGridView1.SelectedRows[0].Cells[0].Value.ToString();//选择的当前行第一列的值，也就是ID
string select_cno = dataGridView1.SelectedRows[0].Cells[1].Value.ToString();//选择的当前行第2列的值，也就是cno
string delete_by_id = "delete from SC where Sno=" + select_id + "AND Cno=" + select_cno;//sql删除语句
SqlCommand cmd = new SqlCommand(delete_by_id, con);
cmd.ExecuteNonQuery();
}
catch
{
MessageBox.Show("请选择正确行！");
}
finally
{
con.Close(); //关闭数据库
}
this.sCTableAdapter.Fill(this.textDataSet2.SC);
}
修改
private void buttonModify_Click(object sender, EventArgs e)//修改分数
{
string StuSno = textBoxsno.Text.Trim();
string StuCno = textBoxcno.Text.Trim();
string StuGrade = textBoxgrade.Text.Trim();
try
{
string insertStr = "";
string insertStr1 = "";
con.Open();
if (StuCno != "")
{
insertStr = "UPDATE SC SET Cno = '" + StuCno + "' WHERE Sno = '" + StuSno + "'" + "AND Grade='" + StuGrade + "'"; //修改课程
SqlCommand cmd = new SqlCommand(insertStr, con);
cmd.ExecuteNonQuery();
}
if (StuGrade != "")
{
insertStr1 = "UPDATE SC SET Grade = '" + StuGrade + "' WHERE Sno = '" + StuSno + "'" + "AND Cno='" + StuCno + "'"; ; //修改成绩
SqlCommand cmd1 = new SqlCommand(insertStr1, con);
cmd1.ExecuteNonQuery();
}
}
catch
{
MessageBox.Show("输入数据违反要求");
}
finally
{
con.Close(); //关闭数据库
}
this.sCTableAdapter.Fill(this.textDataSet2.SC);
}
查询
SqlConnection con = new SqlConnection("Data Source=.;Initial Catalog=Text;Persist Security Info=True;User ID=sa;Password=110023");
private void buttonSearch_Click(object sender, EventArgs e)//查询
{
string StuSno = textBoxsno.Text.Trim();
string StuCno = textBoxcno.Text.Trim();
string StuGrade = textBoxgrade.Text.Trim();
String conn = "Data Source =.; Initial Catalog = Text; Persist Security Info = True;User ID = sa; Password = 110023";
SqlConnection sqlconnection = new SqlConnection(conn);//实例化连接对象
try
{
String select_by_id = "select * from SC where ";
int flag = 0;
sqlconnection.Open();
if (StuSno != "")
{
select_by_id += "Sno='" + StuSno + "'"; flag = 1; //按学号查询
}
if (StuCno != "")
{
if (flag == 0)
{
select_by_id += "Cno='" + StuCno + "'" + " ORDER BY Grade DESC";//按课程号查询
flag = 1;
}
else if (flag == 1)
{ select_by_id += "And Cno='" + StuCno + "'"; } //按学号和课程号查询
}
SqlCommand sqlCommand = new SqlCommand(select_by_id, sqlconnection);
SqlDataReader sqlDataReader = sqlCommand.ExecuteReader();
BindingSource bindingSource = new BindingSource();
bindingSource.DataSource = sqlDataReader;
dataGridView1.DataSource = bindingSource;
}
catch
{
MessageBox.Show("查询语句有误，请认真检查SQL语句!");
}
finally
{
sqlconnection.Close();
}
}
学生课程管理
增加
SqlConnection con = new SqlConnection("Data Source =.; Initial Catalog = Text; Persist Security Info = True;User ID = sa; Password = 110023"); //连接数据库
private void buttonAdd_Click(object sender, EventArgs e)//增加
{
String StuCno = textBoxcno.Text.Trim();
String StuCname = textBoxcname.Text.Trim();
String StuCpno = textBoxcpno.Text.Trim();
String StuCcredit = textBoxccredit.Text.Trim(); //读取需要插入的值
//SqlConnection con = new SqlConnection("Data Source=.;Initial Catalog=STUDENT;Persist Security Info=True;User ID=sa;Password=tangdou");
try
{
con.Open();
string insertStr = "INSERT INTO Course (Cno,Cname,Cpno,Ccredit) " + //拼接字符串
"VALUES ('" + StuCno + "','" + StuCname + "','" + StuCpno + "','" + StuCcredit + "')";
SqlCommand cmd = new SqlCommand(insertStr, con);
cmd.ExecuteNonQuery();
}
catch
{
MessageBox.Show("输入数据违反要求!");
}
finally
{
con.Close();
}
this.courseTableAdapter.Fill(this.textDataSet3.Course);
}
删除
private void buttonDelete_Click(object sender, EventArgs e)//删除
{
try
{
con.Open(); //打开数据库
string select_Cno = dataGridView1.SelectedRows[0].Cells[0].Value.ToString();//选择的当前行第一列的值，也就是Sno
string delete_by_Cno = "DELETE FROM Course WHERE Cno='" + select_Cno + "'";//sql删除语句
SqlCommand cmd = new SqlCommand(delete_by_Cno, con);
cmd.ExecuteNonQuery(); //将增加后的信息直接出来
}
catch
{
MessageBox.Show("请选择正确行！");
}
finally
{
con.Close(); //关闭数据库
}
this.courseTableAdapter.Fill(this.textDataSet3.Course);
}
修改
private void buttonModify_Click(object sender, EventArgs e)//修改
{
string StuCno = textBoxcno.Text.Trim();
string StuCname = textBoxcname.Text.Trim();
string StuCpno = textBoxcpno.Text.Trim();
string StuCcredit = textBoxccredit.Text.Trim();
try
{
string insertStr = "";
string insertStr1 = "";
string insertStr2 = "";
con.Open();
if (StuCname != "")
{
insertStr = "UPDATE Course SET Cname = '" + StuCname + "' WHERE Cno = '" + StuCno + "'"; //修改名字
SqlCommand cmd = new SqlCommand(insertStr, con);
cmd.ExecuteNonQuery();
}
if (StuCpno != "")
{
insertStr1 = "UPDATE Course SET Cpno = '" + StuCpno + "' WHERE Cno = '" + StuCno + "'"; //修改先行课
SqlCommand cmd = new SqlCommand(insertStr1, con);
cmd.ExecuteNonQuery();
}
if (StuCcredit != "")
{
insertStr2 = "UPDATE Course SET Ccredit = '" + StuCcredit + "' WHERE Cno = '" + StuCno + "'"; //修改学分
SqlCommand cmd2 = new SqlCommand(insertStr2, con);
cmd2.ExecuteNonQuery();
}
}
catch
{
MessageBox.Show("输入数据违反要求");
}
finally
{
con.Close(); //关闭数据库
}
this.courseTableAdapter.Fill(this.textDataSet3.Course);
}
查询
private void buttonSearch_Click(object sender, EventArgs e)//查询
{
string StuCno = textBoxcno.Text.Trim();
string StuCname = textBoxcname.Text.Trim();
String conn = "Data Source =.; Initial Catalog = Text; Persist Security Info = True;User ID = sa; Password = 110023";
SqlConnection sqlconnection = new SqlConnection(conn);//实例化连接对象
try
{
sqlconnection.Open();
if (StuCno != "") //按课程号查
{
String select_by_cno = "select * from Course where Cno='" + StuCno + "'";
SqlCommand sqlcommand = new SqlCommand(select_by_cno, sqlconnection);
SqlDataReader sqldatareader = sqlcommand.ExecuteReader();
BindingSource bindingsource = new BindingSource();
bindingsource.DataSource = sqldatareader;
dataGridView1.DataSource = bindingsource;
}
if (StuCname != "") //按课程名查
{
String select_by_cname = "select * from Course where Cname='" + StuCname + "'";
SqlCommand sqlcommand = new SqlCommand(select_by_cname, sqlconnection);
SqlDataReader sqldatareader = sqlcommand.ExecuteReader();
BindingSource bindingsource = new BindingSource();
bindingsource.DataSource = sqldatareader;
dataGridView1.DataSource = bindingsource;
}
}
catch
{
MessageBox.Show("查询语句有误，请认真检查SQL语句");
}
finally
{
sqlconnection.Close();
}
}
- 数据库中的代码
DROP TABLE IF EXISTS SC
DROP TABLE IF EXISTS Student
DROP TABLE IF EXISTS Course
DROP TABLE IF EXISTS UserMessage
CREATE TABLE UserMessage
(
UserID NCHAR(20) PRIMARY KEY,
UserPassWord NCHAR(32) ,
UserMobile NCHAR(11),
UserBirthday datetime,
UserIdentity NCHAR(20),
UserPhoto image
);
CREATE TABLE SysLog
(
UserID NCHAR(20) ,
DateAndTime datetime,
UserOperation NCHAR(200)
);
CREATE TABLE Student
(
Sno CHAR(9) PRIMARY KEY, /* 列级完整性约束条件,Sno是主码*/
Sname CHAR(20) UNIQUE, /* Sname取唯一值*/
Ssex CHAR(2),
Sage SMALLINT,
Sdept CHAR(20)
);
CREATE TABLE Course
(
Cno CHAR(4) PRIMARY KEY,
Cname CHAR(40),
Cpno CHAR(4),
Ccredit SMALLINT,
FOREIGN KEY (Cpno) REFERENCES Course(Cno)
);
CREATE TABLE SC
(
Sno CHAR(9),
Cno CHAR(4),
Grade SMALLINT,
PRIMARY KEY (Sno,Cno), /* 主码由两个属性构成，必须作为表级完整性进行定义*/
FOREIGN KEY (Sno) REFERENCES Student(Sno), /* 表级完整性约束条件，Sno是外码，被参照表是Student */
FOREIGN KEY (Cno)REFERENCES Course(Cno) /* 表级完整性约束条件， Cno是外码，被参照表是Course*/
);
INSERT INTO Student (Sno,Sname,Ssex,Sdept,Sage) VALUES ('201215121','李勇','男','CS',20);
INSERT INTO Student (Sno,Sname,Ssex,Sdept,Sage) VALUES ('201215122','刘晨','女','CS',19);
INSERT INTO Student (Sno,Sname,Ssex,Sdept,Sage) VALUES ('201215123','王敏','女','MA',18);
INSERT INTO Student (Sno,Sname,Ssex,Sdept,Sage) VALUES ('201215125','张立','男','IS',19);
INSERT INTO Student (Sno,Sname,Ssex,Sdept,Sage) VALUES ('201215128','陈冬','男','IS',20);
SELECT * FROM Student
INSERT INTO Course(Cno,Cname,Cpno,Ccredit) VALUES ('1','数据库',NULL,4);
INSERT INTO Course(Cno,Cname,Cpno,Ccredit) VALUES ('2','数学',NULL,4);
INSERT INTO Course(Cno,Cname,Cpno,Ccredit) VALUES ('3','信息系统',NULL,4);
INSERT INTO Course(Cno,Cname,Cpno,Ccredit) VALUES ('4','操作系统',NULL,4);
INSERT INTO Course(Cno,Cname,Cpno,Ccredit) VALUES ('5','数据结构',NULL,4);
INSERT INTO Course(Cno,Cname,Cpno,Ccredit) VALUES ('6','数据处理',NULL,4);
INSERT INTO Course(Cno,Cname,Cpno,Ccredit) VALUES ('7','Pascal语言',NULL,4);
UPDATE Course SET Cpno = '5' WHERE Cno = '1'
UPDATE Course SET Cpno = '1' WHERE Cno = '3'
UPDATE Course SET Cpno = '6' WHERE Cno = '4'
UPDATE Course SET Cpno = '7' WHERE Cno = '5'
UPDATE Course SET Cpno = '6' WHERE Cno = '7'
SELECT * FROM Course
INSERT INTO SC(Sno,Cno,Grade) VALUES ('201215121 ','1',92);
INSERT INTO SC(Sno,Cno,Grade) VALUES ('201215121 ','2',85);
INSERT INTO SC(Sno,Cno,Grade) VALUES ('201215121 ','3',88);
INSERT INTO SC(Sno,Cno,Grade) VALUES ('201215122 ','2',90);
INSERT INTO SC(Sno,Cno,Grade) VALUES ('201215122 ','3',80);
SELECT * FROM SC
//新建触发器
IF(OBJECT_ID('regist_recorder') is not null) -- 判断名为 regist_recorder 的触发器是否存在
DROP TRIGGER regist_recorder
GO
CREATE TRIGGER regist_recorder
ON UserMessage
AFTER
INSERT
AS
declare @UserName nchar(20)
declare @DateTime datetime
declare @UserOperation nchar(200)
select @UserName = system_user
select @DateTime = CONVERT(datetime,GETDATE(),120)
declare @op varchar(10)
select @op=case when exists(select 1 from inserted) and exists(select 1 from deleted)
then 'Update'
when exists(select 1 from inserted) and not exists(select 1 from deleted)
then 'Insert'
when not exists(select 1 from inserted) and exists(select 1 from deleted)
then 'Delete' end
select @UserOperation = @op
INSERT INTO SysLog(UserID,DateAndTime,UserOperation)
VALUES (@UserName,@DateTime,@UserOperation)
视频讲解：C#学生信息管理系统