数据库文件储存

{
public Form1()
{
InitializeComponent();
}
public static string strCon = "Data Source=.;Initial Catalog=calculator;Integrated Security=True";
public  SqlConnection sqlCon = new SqlConnection(strCon);

private void button1_Click(object sender, EventArgs e)
{

sqlCon.Open();
string inster = "insert into Table_1(number,frist,operator,two) values('"+comboBox2.Text+"','"+textBox1.Text+"','"+comboBox1.Text+"','"+textBox3.Text+"')";
SqlCommand sqlCmd =new SqlCommand(inster,sqlCon);
int a =sqlCmd.ExecuteNonQuery();
if (a > 0)
{
MessageBox.Show("数据插入成功");
}
else
{
MessageBox.Show("数据插入失败");
}
string selec = "select * from Table_1";
SqlDataAdapter ds = new SqlDataAdapter(selec, sqlCon);
DataSet sda = new DataSet();
ds.Fill(sda, "Table_1");
DataTable dt = sda.Tables["Table_1"];
dataGridView1.DataSource = dt;
}

private void Form1_Load(object sender, EventArgs e)
{

sqlCon.Open();
string select = "select * from Table_1";
SqlDataAdapter ds = new SqlDataAdapter(select, sqlCon);
DataSet sda = new DataSet();
ds.Fill(sda, "Table_1");
DataTable dt = sda.Tables["Table_1"];
comboBox2.ValueMember = "number";
comboBox2.DataSource = dt.DefaultView;
}

private void button2_Click(object sender, EventArgs e)
{

sqlCon.Open();
string select = "select * from Table_1";
SqlDataAdapter ds = new SqlDataAdapter(select,sqlCon);
DataSet sda = new DataSet();
ds.Fill(sda, "Table_1");
DataTable dt = sda.Tables["Table_1"];
dataGridView1.DataSource = dt;

}

private void button4_Click(object sender, EventArgs e)
{

sqlCon.Open();
string select = "delete from Table_1 where number='" + comboBox2.Text + "'";
SqlCommand sd = new SqlCommand(select,sqlCon);
int a=sd.ExecuteNonQuery();
if (a > 0)
{
MessageBox.Show("数据删除成功");
}
else
{
MessageBox.Show("数据删除失败");
}
string selec = "select * from Table_1";
SqlDataAdapter ds = new SqlDataAdapter(selec, sqlCon);
DataSet sda = new DataSet();
ds.Fill(sda, "Table_1");
DataTable dt = sda.Tables["Table_1"];
dataGridView1.DataSource = dt;
}

private void comboBox2_SelectedIndexChanged(object sender, EventArgs e)
{

sqlCon.Open();
string select = "select frist,operator,two from Table_1 where number='"+comboBox2+"'";
SqlCommand cmd = new SqlCommand(select,sqlCon);
SqlDataReader sdr =cmd.ExecuteReader();

while (sdr.Read())
{
textBox1.Text=sdr["frist"].ToString();
comboBox1.Text = sdr["operator"].ToString();
textBox3.Text = sdr["two"].ToString();

}
}

private void button3_Click(object sender, EventArgs e)
{
calculate sa = new calculate(int.Parse(textBox1.Text), int.Parse(textBox3.Text), comboBox1.Text);
if (sa.answer == int.Parse(textBox4.Text))
{
MessageBox.Show("回答正确");
}
else
{
MessageBox.Show("回答错误");

}
}

}
}

interface chapter
{
int answer { get; }
}
class calculate : chapter
{
private int x1;
private int x2;
private string Operator;
public int result;
public calculate(int x1, int x2, string Operator)
{
this.x1 = x1;
this.x2 = x2;
this.Operator = Operator;

}
public int answer
{
get
{

if (Operator == "+")
{
result = x1 + x2;

}
if (Operator == "-")
{

result = x1 - x2;

}
if (Operator == "*")
{

result = x1 * x2;

}
if (Operator == "/")
{

result = x1 / x2;

}
return result;
}
}

}
}