求代码的注释 多谢!

来源：百度知道 编辑：UC知道 时间：2024/06/07 07:55:00
private void Form1_Load(object sender, EventArgs e)
{
SqlConnection con = new SqlConnection("Data Source=.;Initial Catalog=test;Integrated Security=True");
string sql = "select * from test";
con.Open();
SqlDataAdapter dr = new SqlDataAdapter(sql,con);
DataTable dt = new DataTable();
dr.Fill(dt);
this.dataGridView1.DataSource = dt;
con.Close();
}

private void button1_Click(object sender, EventArgs e)
{
DataTable dt = this.dataGridView1.DataSource as DataTable;
SqlConnection con = new SqlConnection("Data Source=.;Initial Catalog=test;Integrated Security=True");
con.Open();
SqlCommand insertcom = new SqlCommand("insert into test(tname) values(@tname)",con);
insertcom.Paramete

private void Form1_Load(object sender, EventArgs e)
{
SqlConnection con = new SqlConnection("Data Source=.;Initial Catalog=test;Integrated Security=True"); //建立数据库连接
string sql = "select * from test"; //查询所有test表中的数据
con.Open(); //打开数据库连接
SqlDataAdapter dr = new SqlDataAdapter(sql,con); 读取查询出的数据到SqlDataAdapter 对象
DataTable dt = new DataTable(); //新建datatable对象
dr.Fill(dt); 将查出的数据放到datatable对象中
this.dataGridView1.DataSource = dt; 给dataGridView1绑定数据源
con.Close(); //关闭数据库连接
}

private void button1_Click(object sender, EventArgs e)
{
DataTable dt = this.dataGridView1.DataSource as DataTable; //强制转换dataGridView1数据源为datatable
SqlConnection con = new SqlConnection("Data Source=.;Initial Catalog=test;Integrated Security=True");
con.Open();
SqlCommand insertcom = new SqlCommand("insert into test(tname) values(@tname)",con); //插入姓名列
insertcom.Parameters.Add(