1.新建一个WinForm工程:

2.找到工具箱中的数据下面的Chart控件，拖拽到界面上去。

3.在属性里面修改Chart控件Name为cpuChart

4.修改series属性，ChartType选为Spline.

5.最后再加个Button按钮，启动曲线绘制。后台代码Form1.cs如下所示：

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

using System.Threading;
using System.Diagnostics;

namespace CPU_usage
{
    public partial class Form1 : Form
    {
        private Thread cpuThread;
        private double[] cpuArray = new double[80];

        public Form1()
        {
            InitializeComponent();
        }

        private void getPerformanceCounters()
        {
            var cpuPerfCounter = new PerformanceCounter("Processor Information", "% Processor Time", "_Total");
            while(true)
            {
                cpuArray[cpuArray.Length - 1] = Math.Round(cpuPerfCounter.NextValue(), 0);
                Array.Copy(cpuArray, 1, cpuArray, 0, cpuArray.Length - 1);

                if (cpuChart.IsHandleCreated)
                {
                    this.Invoke((MethodInvoker)delegate { UpdateCpuChart(); });
                }
                else
                {
                    //......
                }

                Thread.Sleep(100);

            }

        }

        private void UpdateCpuChart()
        {
            cpuChart.Series["CPU使用率"].Points.Clear();

            for (int i = 0; i < cpuArray.Length - 1; ++i)
            {
                cpuChart.Series["CPU使用率"].Points.AddY(cpuArray[i]);
            }
        }


        private void button1_Click(object sender, EventArgs e)
        {
            cpuThread = new Thread(new ThreadStart(this.getPerformanceCounters));
            cpuThread.IsBackground = true;
            cpuThread.Start();
        }
    }
}

6.编译运行，如下图所示：