C#里怎么把SQL里的数据显示在文本框里？

Question

如图所示，我只写了一半，后面的就不会了。请问后面应该怎么写？因为我是小白，所以请诸位大神详解，感激不尽！

Answer 1

第一步，先建立与数据库的连接

第二步，在program.cs里面写程序

using System;

using System.Collections.Generic;

using System.Configuration;

using System.Data;

using System.Data.SqlClient;

using System.Linq;

using System.Text;

using System.Threading.Tasks;

namespace CaterDal

{

public static class SqliteHelper

{

//从配置文本中读取连接字符串

private static string connStr = "Data Source=数据库的名称;Initial Catalog=SWALL;User ID=SA;Password=666";//是这个数据库没错吧？

public static DataTable GetDataTable(string sql,params SqlParameter[] ps)

{

using (SqlConnection conn=new SqlConnection(connStr))

{

//构造适配器对象

SqlDataAdapter pter=new SqlDataAdapter(sql,conn);

//构造数据表，用于接收查询结果

DataTable dt=new DataTable();

//添加参数

pter.SelectCommand.Parameters.AddRange(ps);

//执行结果

pter.Fill(dt);

//返回结果集

return dt;

}

}

}

}

第三步，在项目里面写程序

private void button4_Click(object sender, EventArgs e)

{

DataTable Dt = SqliteHelper.GetDataTable("select * from jjjj");

dataGridView1.DataSource = Dt;

}

}

}

private void button4_Click(object sender, EventArgs e)

{

DataTable Dt = SqliteHelper.GetDataTable("select * from jjjj");

dataGridView1.DataSource = Dt;

}

}

}

private void button4_Click(object sender, EventArgs e)

{

DataTable Dt = SqliteHelper.GetDataTable("select * from lishiji");

dataGridView1.DataSource = Dt;

}

}

}

Form1.cs项目名

1

private void button4_Click(object sender, EventArgs e)

{

DataTable Dt = SqliteHelper.GetDataTable("select * from jjjj");

dataGridView1.DataSource = Dt;

}

}

}

FROM2.CS项目名

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 System.Data.OleDb;

using CaterDal;

namespace sqlssss

public partial class Form2 : Form

{

public Form2()

{

InitializeComponent();

}

private void button1_Click(object sender, EventArgs e)

{

DataTable Dt = new DataTable();

Dt = SqliteHelper.GetDataTable("select * from lishiji");

DgvQueue.DataSource = Dt;

}

}

}