折騰了好久，蒙圈了很久，終于調(diào)用數(shù)據(jù)庫(kù)成功，小白一個(gè)，把學(xué)習(xí)經(jīng)驗(yàn)分享一下，，希望高手指點(diǎn)。。。

首先你要有C#基礎(chǔ)吧，http://www.runoob.com/csharp/csharp-operators.html；其次你要知道數(shù)據(jù)庫(kù)是干嘛用的，可以百度搜；

安裝VS2017；這個(gè)是C#開(kāi)發(fā)環(huán)境，也可以弄數(shù)據(jù)庫(kù)；
  

然后就新建一個(gè)C#桌面應(yīng)用，畫(huà)一個(gè)按鈕  

數(shù)據(jù)庫(kù)怎么弄呢，https://jingyan.baidu.com/album/9f63fb91893ac3c8410f0e58.html?picindex=1；

窗體應(yīng)用怎么連接數(shù)據(jù)庫(kù)呢  https://www.cnblogs.com/makqiq/p/5882351.html
下圖是我設(shè)置的表，以及窗體查詢(xún)數(shù)據(jù)庫(kù)里的數(shù)據(jù)  
  
點(diǎn)擊運(yùn)行


  
下面附上程序
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 WindowsFormsApp4
{
    public partial class Form1 : Form //窗體1
    {
        private string connectString = @"Data Source=(LocalDB)\MSSQLLocalDB;AttachDbFilename=C:\Users\123\Documents\mydata.mdf;Integrated Security=True;Connect Timeout=30";//這個(gè)是連接數(shù)據(jù)庫(kù)的字符串，右擊你建立的數(shù)據(jù)庫(kù)，屬性，連接字符串復(fù)制過(guò)來(lái)，記得加上@哦

        public Form1()
        {
            InitializeComponent();//初始化
        }

        private void Form1_Load(object sender, EventArgs e)
        {
        }

        private void button1_Click(object sender, EventArgs e)    //按鈕點(diǎn)擊事件
        {
            SqlConnection sqlCnt = new SqlConnection(connectString);//實(shí)例化sqlConnection
            sqlCnt.Open();   //打開(kāi)數(shù)據(jù)庫(kù)
            MessageBox.Show("數(shù)據(jù)庫(kù)已打開(kāi)");//打印數(shù)據(jù)庫(kù)
            SqlCommand command = sqlCnt .CreateCommand();//實(shí)例化SqlCommand
          
          
            command.CommandType = CommandType.Text;    //這個(gè)是執(zhí)行SQL語(yǔ)句
            command.CommandText = "SELECT*FROM dbo.[Table]"; //查詢(xún)你建立的表格
            SqlDataReader reader = command.ExecuteReader();     //執(zhí)行SQL，返回一個(gè)“流”
            while (reader.Read())
            {
                MessageBox.Show(Convert.ToString ( reader["id"])+ Convert.ToString(reader["姓名"]) + Convert.ToString(reader["年齡"]));  // 打印出每個(gè)用戶(hù)的信息
            }



            sqlCnt.Close();//關(guān)閉數(shù)據(jù)庫(kù)
            
          
        }
    }
}