Winform圆形环绕的Loading动画

之前写了一个wpf的圆形环绕的loading动画，现在写一个winform的圆形环绕的loading动画。

1.新建winform项目，添加一个picturebox控件，命名为：picturebox；

2.引用中添加using system.drawing.drawing2d;

3.form窗体命名为：loading，cs全部代码如下：

using system;
using system.collections.generic;
using system.componentmodel;
using system.data;
using system.drawing;
using system.linq;
using system.text;
using system.windows.forms;
using system.collections;
using system.drawing.drawing2d;

namespace circle_processbar
{
    public partial class loading : form
    {
        private int count = -1;
        private arraylist images = new arraylist();
        public bitmap[] bitmap = new bitmap[8];
        private int _value = 1;
        private color _circlecolor = color.red;
        private float _circlesize = 0.8f;
        
        public loading()
        {
            initializecomponent();       
        }

        public color circlecolor
        {
            get { return _circlecolor; }
            set
            {
                _circlecolor = value;
                invalidate();
            }
        }

        public float circlesize
        {
            get { return _circlesize; }
            set
            {
                if (value  4.0f ? 4.0f : value;
                invalidate();
            }
        }

        public bitmap drawcircle(int j)
        {
            const float angle = 360.0f / 8; bitmap map = new bitmap(150, 150);
            graphics g = graphics.fromimage(map);
            
            g.translatetransform(width / 2.0f, height / 2.0f);
            g.rotatetransform(angle * _value);
            g.interpolationmode = interpolationmode.highqualitybicubic;
            g.smoothingmode = smoothingmode.antialias;
            int[] a = new int[8] { 25, 50, 75, 100, 125, 150, 175, 200 };
            for (int i = 1; i 

4.效果如图：