c#开发学习之listview连接SQLserver并将数据放到listview里显示

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

namespace Wpf
{
    public partial class UserCRUDForm : Form
    {
        public UserCRUDForm()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {

            try
            {
                showdata();

            } catch (Exception ex) {
                MessageBox.Show(ex.Message);

            }
        }

        private void showdata()
        {
            listView1.Items.Clear();
            listView1.Columns.Clear();
            //编辑表头
            listView1.Columns.Add("编号");
            listView1.Columns.Add("姓名");
            listView1.Columns.Add("密码");

            string conn = "server=.;database=test" + ";uid=sa;password=3044136609";
            SqlConnection sqlcon = new SqlConnection(conn);

            string sql = "select * from 管理员";
            SqlDataAdapter sqlda = new SqlDataAdapter(sql, sqlcon);

            DataSet ds = new DataSet();
            sqlda.Fill(ds);

            string[] str=new string[1000];
            foreach (DataRow dr in ds.Tables[0].Rows)
            {
                str[0] = dr["id"].ToString();
                str[1] = dr["name"].ToString();
                str[2] = dr["password"].ToString();
                //listview的第一列可以认为就是item.Subitenms[0]
                ListViewItem item = new ListViewItem(str[0]);
                item.SubItems.Add(str[1]);
                item.SubItems.Add(str[2]);
                listView1.Items.Add(item); 
            }
        }

        private void button2_Click(object sender, EventArgs e)
        {
            try
            {
                deletedata();
            }catch(Exception ex)
            {
                MessageBox.Show(ex.Message);
            }

        }

        private void deletedata()
        {
            //数据库连接操作
            string conn = "server=.;database=test" + ";uid=sa;password=3044136609";
            SqlConnection sqlcon = new SqlConnection(conn);

            //获取一行的各列值，以后可以将这些列值封装到实体类
            string id = listView1.SelectedItems[0].SubItems[0].Text;
            string name = listView1.SelectedItems[0].SubItems[1].Text;
            MessageBox.Show(id + "  " + name);

            string sql = "delete  from 管理员 where id="+id+";";
            //数据库打开操作
            sqlcon.Open();
            //实例化sqlcommand对象
            SqlCommand cmd=new SqlCommand(sql, sqlcon);

            int num=cmd.ExecuteNonQuery();
            if(num > 0)
            {
                MessageBox.Show("删除成功");
                showdata();
            }
            
        }
    }
}