c#仪表指针旋转

[qq_37834095]

请教下，鼠标事件里怎么让鼠标在绘制的仪表上移动，仪表指针也会随着旋转啊，请求指导。。。谢谢
我是在图片上获取鼠标的位置的，把这横轴范围映射到对应0到100的范围里，发现这样会出现误差。。。；有好点的实现方法吗

[lindexi_gd]

你看看这个是否符合你需要

win10 uwp 车表盘 径向规

[desperaso]

按照盘子的形状调整长度（圆上的点），这里省事就按鼠标位置画了个线，就这么个意思了

public Form1()
        {
            InitializeComponent();
            
            bool press = false;
            Point[] line_point = new Point[] { new Point(100, 100), new Point(100, 20) };
            Panel panel = new Panel()
            {
                Size = new Size(200, 200),
                Location = new Point(10,10),
                BackColor = Color.White,
            };
            panel.Paint += (s,e)=> 
            {
                Graphics g = e.Graphics;
                g.SmoothingMode = SmoothingMode.AntiAlias;
                Pen pen = new Pen(Color.SteelBlue, 2);
                g.DrawLine(pen, line_point[0], line_point[1]);
            };
            panel.MouseDown += (s, e) => { press = true; line_point[1] = new Point(e.X, e.Y); panel.Invalidate(); };
            panel.MouseUp += (s, e) => { press = false; };
            panel.MouseMove += (s, e) => { if (press) { line_point[1] = new Point(e.X, e.Y); panel.Invalidate(); } };
            this.Controls.Add(panel);
        }

[Bridge_go]

http://www.devcomponents.com/kb2/?p=989

[qq_37834095]

哎，。。。看看这个水平移动条呢？我画了一个
是在控件里画的，我移动鼠标得到的绿色部分无法刷新呢
我的代码如下：
private void panel1_Paint(object sender, PaintEventArgs e)
{
Graphics g;
g = panel1.CreateGraphics();
Pen pn1 = new Pen(Color.FromArgb(200, 200, 0), panel1.Height);
Point cer = new Point(0, 0);
Size re = new Size(panel1.Width / 16, panel1.Height);
g.DrawRectangle(pn1, cer.X, cer.Y, re.Width, re.Height);

}

private void panel1_MouseMove(object sender, MouseEventArgs e)
{
if (e.Button == MouseButtons.Left)//鼠标在该控件上按下
{

Graphics g = panel1.CreateGraphics();

Pen pn1 = new Pen(Color.FromArgb(90, 200, 80), panel1.Height);
Point cer = new Point(0, 0);

newX = cer.X+e.X;
newY = cer.Y;
Invalidate();
}

}

protected override void OnPaint(PaintEventArgs e)
{//自定义重绘
base.OnPaint(e);
Graphics g;
g = panel1.CreateGraphics();
Pen pn1 = new Pen(Color.FromArgb(90, 200, 80), panel1.Height);
Size re = new Size(panel1.Width / 16, panel1.Height);
g.DrawRectangle(pn1, newX, newY, re.Width, re.Height);

}
如果我用Refresh()也不会刷新呢，绿色部分只会增加不会减少呢？

[qq_37834095]

[quote=引用 2 楼 desperaso 的回复:]
按照盘子的形状调整长度（圆上的点），这里省事就按鼠标位置画了个线，就这么个意思了

麻烦看看我这个是什么原因啊

[Bridge_go]

只要这一个事件

private void panel1_MouseMove(object sender, MouseEventArgs e)
{
    if (e.Button == MouseButtons.Left)//鼠标在该控件上按下
    {
        Graphics g = panel1.CreateGraphics();
        g.Clear(this.panel1.BackColor);
        g.FillRectangle(new SolidBrush(Color.FromArgb(90, 200, 80)), 0, 0, e.X, this.panel1.Height);
    }
}

[qq_37834095]

啊，你都不重绘吗？我现在可以了，让重绘函数实现了动作，我再想把它作为滑块，显示数值就可以关联仪表指针的值