标签：man command des view dataset build eve color ESS
数据库为sqlserver，结构如下：
数据库数据
开发工具为visual studio2013
首先先拖动控件来搭建出简单的页面如下，其中增删改查按钮这些控件都在toolstripe中，下面是DataGridView控件以显示数据库中数据
设置控件属性达到如下效果。
结构：
源代码：
连接数据库语句DBhelper.cs：(注意添加using System.Data.SqlClient;)
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Data;
using System.Data.SqlClient;
namespace xueshengchengjiguanli
{
class DBhelper
{
private string connString ="server=.;database=student1;user=sa;pwd=root;";//连接数据库自己的用户名密码
private SqlConnection connection;
public SqlConnection Connection
{
get
{
if (connection == null)
{
connection = new SqlConnection(connString);
}
return connection;
}
}
//打开数据库连接
public void OpenConnection()
{
if (Connection.State == ConnectionState.Closed)
{
Connection.Open();
}
else if (Connection.State == ConnectionState.Broken)
{
Connection.Close();
Connection.Open();
}
}
//关闭数据库
public void CloseConnection()
{
if (Connection.State == ConnectionState.Open || Connection.State == ConnectionState.Broken)
{
Connection.Close();
}
}
}
}
主页面Form1.cs
1 using System; 2 using System.Collections.Generic; 3 using System.ComponentModel; 4 using System.Data; 5 using System.Data.SqlClient; 6 using System.Drawing; 7 using System.Linq; 8 using System.Text; 9 using System.Threading.Tasks; 10 using System.Windows.Forms; 11 12 namespace xueshengchengjiguanli 13 { 14 public partial class Form1 : Form 15 { 16 public Form1() 17 { 18 InitializeComponent(); 19 } 20 DataSet ds = new DataSet(); 21 //获取数据方法 22 private void GetDB() 23 { 24 ds = new DataSet(); 25 DBhelper dbhelper = new DBhelper(); 26 try 27 { 28 string sql = @"Select Sno 学号,Sname 姓名,Sclass 班级,SChinese 语文,SMath 数学,SEnglish 英语,SChinese+SMath+SEnglish 总分, 29 (SChinese+SMath+SEnglish)/3 平均分 from Score order by SChinese+SMath+SEnglish desc"; 30 SqlDataAdapter adapter = new SqlDataAdapter(sql, dbhelper.Connection); 31 adapter.Fill(ds, "Score"); 32 this.dgv.DataSource = this.ds.Tables["Score"]; 33 } 34 catch (Exception) 35 { 36 37 MessageBox.Show("数据库操作错误", "系统提示", MessageBoxButtons.OK, MessageBoxIcon.Information); 38 } 39 } 40 41 //退出按钮被点击 42 private void tsbtnExit_Click(object sender, EventArgs e) 43 { 44 this.Close(); 45 } 46 //窗体加载事件 47 private void Form1_Load(object sender, EventArgs e) 48 { 49 GetDB(); 50 } 51 //添加按钮被点击 52 private void tsbtnIn_Click(object sender, EventArgs e) 53 { 54 Edit ed = new Edit(); 55 ed.ShowDialog(); 56 GetDB(); 57 } 58 //修改按钮被点击 59 private void tsbtnUpdate_Click(object sender, EventArgs e) 60 { 61 Edit ed = new Edit(); 62 ed.Sno = Convert.ToInt32(this.dgv.SelectedCells[0].Value); 63 ed.ShowDialog(); 64 GetDB(); 65 } 66 //删除按钮被点击 67 private void tsbtnDelete_Click(object sender, EventArgs e) 68 { 69 Delete(); 70 } 71 //删除方法 72 private void Delete() 73 { 74 75 if (this.dgv.CurrentRow != null) 76 { 77 DialogResult dr = MessageBox.Show("确定要删除：" + dgv.CurrentRow.Cells[1].Value +"相关成绩信息", "系统提示", MessageBoxButtons.OKCancel, MessageBoxIcon.Information); 78 if (dr == DialogResult.OK) 79 { 80 DBhelper helper = new DBhelper(); 81 try 82 { 83 //sql语句 84 StringBuilder sb = new StringBuilder(); 85 sb.AppendFormat("delete from Score where Sno={0}", Convert.ToInt32(dgv.CurrentRow.Cells[0].Value)); 86 //执行工具 87 SqlCommand cmd = new SqlCommand(sb.ToString(), helper.Connection); 88 //打开数据库连接 89 helper.OpenConnection(); 90 //执行 91 int result = cmd.ExecuteNonQuery(); 92 if (result == 1) 93 { 94 MessageBox.Show("删除成功", "系统提示", MessageBoxButtons.OK, MessageBoxIcon.Information); 95 //重新绑定dgv 96 this.GetDB(); 97 } 98 } 99 catch (Exception) 100 { 101 102 MessageBox.Show("数据库操作失败", "系统提示", MessageBoxButtons.OK, MessageBoxIcon.Information); 103 } 104 finally 105 { 106 helper.CloseConnection(); 107 } 108 } 109 } 110 111 } 112 //查询按钮被点击 113 private void toolStripButton1_Click(object sender, EventArgs e) 114 { 115 this.Search(); 116 }
//查询方法 117 private void Search() 118 { 119 ds = new DataSet(); 120 DBhelper dbHelper = new DBhelper(); 121 try 122 { 123 string strSql = @"Select Sno 学号,Sname 姓名,Sclass 班级,SChinese 语文,SMath 数学,SEnglish 英语,SChinese+SMath+SEnglish 总分, 124 (SChinese+SMath+SEnglish)/3 平均分 from Score 125 where 1=1"; 126 if (toolStripTextBox1.Text.Trim() != null && toolStripTextBox1.Text.Trim().Length > 0) 127 { 128 strSql += " and Sname like ‘%" + toolStripTextBox1.Text.Trim() + "%‘"; 129 } 130 if (toolStripTextBox2.Text.Trim() != null && toolStripTextBox2.Text.Trim().Length > 0) 131 { 132 strSql += " and Sclass like ‘%" + toolStripTextBox2.Text.Trim() + "%‘"; 133 } 134 strSql += "order by SChinese+SMath+SEnglish desc"; 135 SqlDataAdapter adapter = new SqlDataAdapter(strSql, dbHelper.Connection); 136 adapter.Fill(ds, "score"); 137 this.dgv.DataSource = this.ds.Tables["score"]; 138 } 139 catch (Exception) 140 { 141 MessageBox.Show("数据库操作错误！", "系统提示", MessageBoxButtons.OK, MessageBoxIcon.Information); 142 } 143 } 144 145 146 } 147 }
编辑页面Edit.cs
页面：
1 using System; 2 using System.Collections.Generic; 3 using System.ComponentModel; 4 using System.Data; 5 using System.Data.SqlClient; 6 using System.Drawing; 7 using System.Linq; 8 using System.Text; 9 using System.Threading.Tasks; 10 using System.Windows.Forms; 11 12 namespace xueshengchengjiguanli 13 { 14 public partial class Edit : Form 15 { 16 //变量 17 public int Sno = -1; 18 DataSet ds = new DataSet(); 19 public Edit() 20 { 21 InitializeComponent(); 22 } 23 //窗体加载 24 private void Edit_Load(object sender, EventArgs e) 25 { 26 if (Sno == -1)//没有被选定的行数 27 { 28 29 } 30 else//修改 31 { 32 GetInfo(); 33 this.btnSave.Text = "修改"; 34 } 35 } 36 //保存按钮 37 private void btnSave_Click(object sender, EventArgs e) 38 { 39 if (CheckItem()) 40 { 41 if (this.Sno == -1)//新增 42 { 43 if (CheckSnoExit()) 44 { 45 InsertDB(); 46 } 47 } 48 else//更新 49 { 50 UpdateScore(); 51 } 52 } 53 } 54 //非空验证 55 private bool CheckItem() 56 { 57 bool checkValue = true; 58 if (this.textBox1.Text.Trim().Length == 0) 59 { 60 MessageBox.Show("学号不能为空", "系统提示", MessageBoxButtons.OK, MessageBoxIcon.Information); 61 checkValue = false; 62 this.textBox1.Text = " "; 63 } 64 return checkValue; 65 } 66 //增加方法 67 //查重 68 private bool CheckSnoExit() 69 { 70 bool exit = true; 71 DBhelper dbhelper = new DBhelper(); 72 try 73 { 74 StringBuilder sb = new StringBuilder(); 75 sb.AppendFormat("select * from Score where Sno=‘{0}‘", textBox1.Text.Trim()); 76 SqlCommand cmd = new SqlCommand(sb.ToString(), dbhelper.Connection); 77 dbhelper.OpenConnection(); 78 SqlDataReader reader = cmd.ExecuteReader(); 79 if (reader.Read()) 80 { 81 MessageBox.Show("该学号已存在", "系统提示", MessageBoxButtons.OK, MessageBoxIcon.Information); 82 exit = false; 83 } 84 reader.Close(); 85 } 86 catch (Exception) 87 { 88 MessageBox.Show("数据库操作错误", "系统提示", MessageBoxButtons.OK, MessageBoxIcon.Information); 89 } 90 finally 91 { 92 dbhelper.CloseConnection(); 93 } 94 return exit; 95 } 96 //执行增加 97 private void InsertDB() 98 { 99 DBhelper helper = new DBhelper(); 100 try 101 { 102 //SQL语句 103 StringBuilder sb = new StringBuilder(); 104 sb.AppendLine("insert into Score"); 105 sb.AppendFormat("values(‘{0}‘,‘{1}‘,‘{2}‘,‘{3}‘,‘{4}‘,‘{5}‘)", textBox1.Text.Trim(),textBox2.Text.Trim(),comboBox1.Text.Trim(),textBox4.Text.Trim(),textBox5.Text.Trim(),textBox6.Text.Trim()); 106 //执行工具 107 SqlCommand cmd = new SqlCommand(sb.ToString(), helper.Connection); 108 //打开连接 109 helper.OpenConnection(); 110 //执行 111 int result = cmd.ExecuteNonQuery(); 112 if (result > 0) 113 { 114 MessageBox.Show("添加成功", "系统提示", MessageBoxButtons.OK, MessageBoxIcon.Information); 115 this.Close(); 116 } 117 } 118 catch (Exception) 119 { 120 MessageBox.Show("添加数据库操作错误", "系统提示", MessageBoxButtons.OK, MessageBoxIcon.Information); 121 } 122 finally 123 { 124 helper.CloseConnection(); 125 } 126 } 127 128 //通过ID查找类别 129 private void GetInfo() 130 { 131 DBhelper dbhelper = new DBhelper(); 132 try 133 { 134 //SQL语句 135 StringBuilder sb = new StringBuilder(); 136 sb.AppendLine("select Sno,Sname,Sclass,SChinese,SMath,SEnglish"); 137 sb.AppendLine("from Score"); 138 sb.AppendFormat("where Sno={0}", Sno); 139 //执行工具 140 SqlCommand cmd = new SqlCommand(sb.ToString(), dbhelper.Connection); 141 //打开连接 142 dbhelper.OpenConnection(); 143 //执行 144 SqlDataReader reader = cmd.ExecuteReader(); 145 if (reader.Read()) 146 { 147 textBox1.Text = reader["Sno"].ToString(); 148 textBox2.Text = reader["Sname"].ToString(); 149 comboBox1.Text = reader["Sclass"].ToString(); 150 textBox4.Text = reader["SChinese"].ToString(); 151 textBox5.Text = reader["SMath"].ToString(); 152 textBox6.Text = reader["SEnglish"].ToString(); 153 } 154 reader.Close(); 155 } 156 catch (Exception) 157 { 158 MessageBox.Show("操作错误", "系统提示", MessageBoxButtons.OK, MessageBoxIcon.Information); 159 } 160 finally 161 { 162 dbhelper.CloseConnection(); 163 } 164 165 } 166 //修改 167 private void UpdateScore() 168 { 169 DBhelper helper = new DBhelper(); 170 try 171 { 172 StringBuilder sql = new StringBuilder(); 173 //修改数据库语句 174 sql.AppendLine("update Score"); 175 sql.AppendFormat("set Sname=‘{0}‘,Sclass=‘{1}‘,SChinese=‘{2}‘,SMath=‘{3}‘,SEnglish=‘{4}‘", textBox2.Text.Trim(), comboBox1.Text.Trim(), textBox4.Text.Trim(), textBox5.Text.Trim(), textBox6.Text.Trim()); 176 sql.AppendFormat("where Sno={0}", Sno); 177 //执行工具 178 SqlCommand cmd = new SqlCommand(sql.ToString(), helper.Connection); 179 //打开数据库连接 180 helper.OpenConnection(); 181 //执行 182 int result = cmd.ExecuteNonQuery(); 183 //判断 184 if (result == 1) 185 { 186 187 MessageBox.Show("修改成功", "系统提示", MessageBoxButtons.OK, MessageBoxIcon.Information); 188 this.Close(); 189 } 190 else 191 { 192 193 MessageBox.Show("修改失败", "系统提示", MessageBoxButtons.OK, MessageBoxIcon.Information); 194 } 195 } 196 catch (Exception) 197 { 198 199 MessageBox.Show("修改数据库操作错误", "系统提示", MessageBoxButtons.OK, MessageBoxIcon.Information); 200 } 201 finally 202 { 203 helper.CloseConnection(); 204 } 205 206 } 207 //取消按钮 208 private void button2_Click(object sender, EventArgs e) 209 { 210 this.Close(); 211 } 212 } 213 }
运行结果如下：
标签：man command des view dataset build eve color ESS
原文地址：https://www.cnblogs.com/qq1793033075/p/12188268.html
