c# - 如何在图片框控件中突出显示图像的特定部分

Question

我想在应用程序运行时突出显示图片框控件中图像的特定部分。如何使用 C# 实现这个？

Answer 1

这里有一个示例，当用户将鼠标悬停在图像上时，绘制一个 alpha 矩形悬停在图片框上。请注意，您可以根据需要突出显示图片。

public partial class Form2 : Form
{
    private Rectangle mHoverRectangle = Rectangle.Empty;
    private const int HOVER_RECTANGLE_SIZE = 20;

    public Form2()
    {
        InitializeComponent();

        pictureBox.MouseMove += new MouseEventHandler(pictureBox_MouseMove);
        pictureBox.Paint += new PaintEventHandler(pictureBox_Paint);
        pictureBox.MouseLeave += new EventHandler(pictureBox_MouseLeave);
    }

    void pictureBox_MouseLeave(object sender, EventArgs e)
    {
        mHoverRectangle = Rectangle.Empty;
    }

    void pictureBox_Paint(object sender, PaintEventArgs e)
    {
        if (mHoverRectangle != Rectangle.Empty)
        {
            using (Brush b = new SolidBrush(Color.FromArgb(150, Color.White)))
            {
                e.Graphics.FillRectangle(b, mHoverRectangle);
            }
        }
    }

    void pictureBox_MouseMove(object sender, MouseEventArgs e)
    {
        mHoverRectangle = new Rectangle(
            e.Location.X - HOVER_RECTANGLE_SIZE / 2,
            e.Location.Y - HOVER_RECTANGLE_SIZE / 2,
            HOVER_RECTANGLE_SIZE,
            HOVER_RECTANGLE_SIZE);

        pictureBox.Invalidate();
    }

希望对你有帮助