如何在鼠標移動事件中實時在pictureBox1中的圖像上繪制紅色像素？

Question

我正在嘗試在移動鼠標時以紅色繪制像素，以便鼠標 cursor 在 pictureBox1 內部繪制一個像素。

public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();

            pictureBox1.Image = Properties.Resources._image;
        }

        private void Form1_Load(object sender, EventArgs e)
        {

        }

        private void button1_Click(object sender, EventArgs e)
        {
           
        }

        private void pictureBox1_MouseMove(object sender, MouseEventArgs e)
        {
            label1.Text = String.Format("X: {0}; Y: {1}", e.X, e.Y);

            Bitmap bmp = new Bitmap(pictureBox1.Image);

            for(int x = 0; x < bmp.Width; x++)
            {
                for(int y = 0; y < bmp.Height; y++)
                {
                    bmp.SetPixel(e.X, e.Y, Color.Red);
                }
            }

            bmp.Dispose();
        }

這非常慢，並且不會以紅色繪制像素。

Answer 1

這在鼠標移動事件中起作用：

private void pictureBox1_MouseMove(object sender, MouseEventArgs e)
        {
            label1.Text = String.Format("X: {0}; Y: {1}", e.X, e.Y);
            Bitmap bmp = new Bitmap(pictureBox1.Image);
            bmp.SetPixel(e.X, e.Y, Color.Red);
            pictureBox1.Image = bmp;
        }