database conecting c# 2015

Question

i am Beginner programmer i wont to Connect database to windows form (textbox1,textbox2)

.my kod.not works

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.SqlClient;

namespace WindowsFormsApplication7

{

public partial class Form1 : Form

{

public Form1()

{

InitializeComponent();

}

private void Form1_Load(object sender, EventArgs e)

{

// TODO: This line of code loads data into the 'database1DataSet.Students' table. You can move, or remove it, as needed.

this.studentsTableAdapter.Fill(this.database1DataSet.Students);

}

private void button1_Click(object sender, EventArgs e)

{

SqlConnection cn = new SqlConnection();//?????????????????????????????????????????

try

{

string sql = "INSSERT INTO Students(Student_Id,Studentname) values(" + textBox1.Text+",'"+textBox2.Text+")";

SqlCommand exeSql = new SqlCommand(sql, cn);

cn.Open();

exeSql.ExecuteNonQuery();

}

catch(Exception ex)

{

}

finally

{

}

}

}

}