数据库增删改查

属性:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Data
{
    public  class cdata
    {
        private string Cno;

        public string Cno1
        {
            get { return Cno; }
            set { Cno = value; }
        }
        private string Cname;

        public string Cname1
        {
            get { return Cname; }
            set { Cname = value; }
        }
        private string Tno;

        public string Tno1
        {
            get { return Tno; }
            set { Tno = value; }
        }
    }
}

　　方法:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Data;
using System.Data.SqlClient;


namespace Da
{
     public  class cda
    {
         private SqlConnection conn;
         private SqlCommand cmd;

         public cda()
         {
             conn = new SqlConnection("server=.;database=kl;user=sa;pwd=123");
             cmd = conn.CreateCommand();
         }
         public void insert(cdata dt)
         {
             cmd.CommandText = "insert into course values(@Cno,@Cname,@Tno)";
             cmd.Parameters.Clear();
             cmd.Parameters.Add("@Cno", dt.Cno1);
             cmd.Parameters.Add("@Cname", dt.Cname1);
             cmd.Parameters.Add("@Tno", dt.Tno1);
             conn.Open();
             cmd.ExecuteNonQuery();
             conn.Close();
         }
         public void update(cdata dt)
         {
             cmd.CommandText = "update course set Cname=@Cname,Tno=@Tno where Cno=@Cno";
             cmd.Parameters.Clear();
             cmd.Parameters.Add("@Cno", dt.Cno1);
             cmd.Parameters.Add("@Cname", dt.Cname1);
             cmd.Parameters.Add("@Tno", dt.Tno1);
             conn.Open();
             cmd.ExecuteNonQuery();
             conn.Close();
         }
         public void delete(string Cno)
         {
             cmd.CommandText = "delete from course where Cno=@Cno";
             cmd.Parameters.Add("@Cno", Cno);
             conn.Open();
             cmd.ExecuteNonQuery();
             conn.Close();
         }
         //-----------------------------------------------查询
         public List<cdata> select()
         {
             List<cdata> list = null;
             cmd.CommandText = "select *from course";
             conn.Open();
             SqlDataReader dr = cmd.ExecuteReader();
             if (dr.HasRows)
             {
                 list = new List<cdata>();
                 while (dr.Read())
                 {
                     cdata dt = new cdata();
                     dt.Cno1 = dr["Cno"].ToString();
                     dt.Cname1 = dr["Cname"].ToString();
                     dt.Tno1 = dr["Tno"].ToString();
                     list.Add(dt);
                 }
             }
             cmd.Dispose();
             conn.Close();
             return list;
         }
         public cdata select(String Cno)
         {
             cdata list = null;
             cmd.CommandText = "select *from course where Cno=@Cno";
             cmd.Parameters.Clear();
             cmd.Parameters.Add("@Cno", Cno);
             conn.Open();
             SqlDataReader dr = cmd.ExecuteReader();
             if (dr.HasRows)
             {
                 list = new cdata();
                 if (dr.Read())
                 {
                     cdata dt = new cdata();
                     dt.Cno1 = dr["Cno"].ToString();
                     dt.Cname1 = dr["Cname"].ToString();
                     dt.Tno1 = dr["Tno"].ToString();
                 }
             }
             conn.Close();
             cmd.Dispose();
             return list;
         }
         public List<cdata> select(string Cno,string Cname,string Tno)
         {
             List<cdata> list = null;
             cmd.CommandText = "select *from course where Cno like ‘%" + Cno + "%‘ and Cname like ‘%" + Cname + "%‘ and Tno like ‘%" + Tno + "%‘";
             conn.Open();
             SqlDataReader dr = cmd.ExecuteReader();
             if (dr.HasRows)
             {
                 list = new List<cdata>();
                 while (dr.Read())
                 {
                     cdata dt = new cdata();
                     dt.Cno1 = dr["Cno"].ToString();
                     dt.Cname1 = dr["Cname"].ToString();
                     dt.Tno1 = dr["Tno"].ToString();
                     list.Add(dt);
                 }
             }
             cmd.Dispose();
             conn.Close();
             return list;
         }
    }
}

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using Da;
using Data;


namespace WindowsFormsApplication1
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }
        //private string Cno;
        //public Form1(string cno)
        //{
        //    InitializeComponent();
        //    Cno = cno;
        //}
        private void button1_Click(object sender, EventArgs e)//查询
        {
            List<cdata> list = new cda().select();
            bindListView(list);
        }
        //查看首先获取显示数据
        public void bindListView(List<cdata> list)
        {
            listView1.Columns.Clear();
            listView1.Columns.Add("Cno");
            listView1.Columns.Add("Cname");
            listView1.Columns.Add("Tno");

            listView1.Items.Clear();
            foreach (cdata dt in list)
            {
                ListViewItem l = new ListViewItem();
                l.Text = dt.Cno1;
                l.SubItems.Add(dt.Cname1);
                l.SubItems.Add(dt.Tno1);
                listView1.Items.Add(l);
            }
        }

        private void button4_Click(object sender, EventArgs e)//删除
        {
            if (listView1.SelectedItems.Count>0)
            {
                string Cno = listView1.SelectedItems[0].Text;
                new cda().delete(Cno);
                //删除后重新绑定数据   
                List<cdata> list = new cda().select();
                bindListView(list);
            }
            else
            {
                MessageBox.Show("请选中要删除的内容");
            }
        }

        private void button7_Click(object sender, EventArgs e)//条件查询
        {
            List<cdata> list = new cda().select(textBox4.Text, textBox5.Text, textBox6.Text);
            bindListView(list);
        }

        private void button3_Click(object sender, EventArgs e)//增加
        {
            textBox1.Enabled = true;
            textBox1.Text = "";
            textBox2.Text = "";
            textBox3.Text = "";
        }

        private void button5_Click(object sender, EventArgs e)//确认增加
        {
            cdata dt = new cdata();
            dt.Cno1 = textBox1.Text;
            dt.Cname1 = textBox2.Text;
            dt.Tno1 = textBox3.Text;
            new cda().insert(dt);
        }

        private void button2_Click(object sender, EventArgs e)//修改
        {
            if (listView1.SelectedItems.Count > 0)
            {
                string Cno = listView1.SelectedItems[0].SubItems[0].Text;
                string Cname = listView1.SelectedItems[0].SubItems[1].Text;
                string Tno = listView1.SelectedItems[0].SubItems[2].Text;
              
                textBox1.Text = Cno;
                textBox2.Text = Cname;
                textBox3.Text = Tno;
            }
            else
            {
                MessageBox.Show("请选中要修改的内容");
            }
        }
        private void button6_Click(object sender, EventArgs e)//确认修改
        {
            cdata dt = new cdata();
            dt.Cno1 = textBox1.Text;
            dt.Cname1 = textBox2.Text;
            dt.Tno1 = textBox3.Text;
            new cda().update(dt);
        }
        
    }
}

数据库增删改查

标签：