c# Parallel并行运算

string str = "";
            DataTable dt=new DataTable();
            dt.Columns.Add("name", typeof(System.String));

            for (int i = 0; i <10000; i++)
            {
                DataRow drt = dt.NewRow();
                drt[0] = "hh"+i;
                dt.Rows.Add(drt);
            }
            DataRow[] rules = new DataRow[dt.Rows.Count];
            dt.Rows.CopyTo(rules, 0);
            // 第一个
            Stopwatch watch1 = new Stopwatch();
            watch1.Start();
            Parallel.ForEach<DataRow>(rules, (dr) =>
            {
                str += dr[0];
                str += dr[0];
            });
            watch1.Stop();
            txtWat1.Text = watch1.ElapsedMilliseconds.ToString();

普通运算的方法

// 第二个
            Stopwatch watch2 = new Stopwatch();
            watch2.Start();
            for (int i = 0; i < dt.Rows.Count; i++)
            {
                DataRow dr = dt.Rows[i];
                str += dr[0];
                str += dr[0];
            }
            watch2.Stop();
            txtWat2.Text = watch2.ElapsedMilliseconds.ToString();

最后的时间对比