string str=ConfigurationManager.connectionstrings[""].connectionstring;
SqlConnection con=new sqlConnection(str);
SqlDataAdapter adapter=new salDataAdapter(cmd );
DataTable dt=new DataTable();
adapter.fill(dt);
con.close();
con.dispose();
cmd.dispose();
SqlConnection con=new sqlConnection(str);
SqlCommand cmd=con.creatcommand;
Cmd.CommandText = "数据库查询语句";
Cmd.Parameters.AddWithValue("@name", name.Text);
SqlDataAdapter adapter=new salDataAdapter(cmd );
DataTable dt=new DataTable();
adapter.fill(dt);
con.close();
con.dispose();
cmd.dispose();