using statement v.s. try-catch-finally

Class1-disassembled.cs

using System;
using System.Data;
using System.Data.Common;
using System.Data.SqlClient;

namespace UsingIlTest
{
    public class Class1
    {
        public Class1()
        {
        }

        public void TryCatchFinally()
        {
            DataSet ds = new DataSet();
            SqlConnection conn = new SqlConnection("fake");
            try
            {
                try
                {
                    SqlCommand cmd = new SqlCommand()
                    {
                        CommandText = "SELECT * FROM whatever",
                        CommandType = CommandType.StoredProcedure,
                        Connection = conn
                    };
                    conn.Open();
                    (new SqlDataAdapter(cmd)).Fill(ds);
                }
                catch (Exception exception)
                {
                }
            }
            finally
            {
                conn.Close();
            }
        }

        public void Using()
        {
            DataSet ds = new DataSet();
            using (SqlConnection conn = new SqlConnection("fake"))
            {
                SqlCommand cmd = new SqlCommand()
                {
                    CommandText = "SELECT * FROM whatever",
                    CommandType = CommandType.StoredProcedure,
                    Connection = conn
                };
                conn.Open();
                (new SqlDataAdapter(cmd)).Fill(ds);
                conn.Close();
            }
        }
    }
}

Class1.cs

using System;
using System.Collections.Generic;
using System.Data;
using System.Data.SqlClient;
using System.IO;
using System.Linq;
using System.Security.Permissions;
using System.Text;
using System.Threading.Tasks;

namespace UsingIlTest
{
    public class Class1
    {
        public void Using()
        {
            DataSet ds = new DataSet();
            using (SqlConnection conn = new SqlConnection("fake"))
            {
                SqlCommand cmd = new SqlCommand();
                cmd.CommandText = "SELECT * FROM whatever";
                cmd.CommandType = CommandType.StoredProcedure;
                cmd.Connection = conn;
                
                conn.Open();

                var adapter = new SqlDataAdapter(cmd);
                adapter.Fill(ds);

                conn.Close();
            }
        }

        public void TryCatchFinally()
        {
            DataSet ds = new DataSet();
            SqlConnection conn = new SqlConnection("fake");

            try
            {
                SqlCommand cmd = new SqlCommand();
                cmd.CommandText = "SELECT * FROM whatever";
                cmd.CommandType = CommandType.StoredProcedure;
                cmd.Connection = conn;

                conn.Open();

                var adapter = new SqlDataAdapter(cmd);
                adapter.Fill(ds);
            }
            catch (Exception)
            {
            }
            finally
            {
                conn.Close();
            }
        }
    }
}

System.Data.SqlClient.SqlConnection-diassembled-snippet.cs

protected override void Dispose(bool disposing)
{
	if (disposing)
	{
		this._userConnectionOptions = null;
		this._poolGroup = null;
		this.Close();
	}
	this.DisposeMe(disposing);
	base.Dispose(disposing);
}