如何用c＃制作两个透明层？

有三个连续的图层，
picturebox1(.jpg) -> label1 -> picturebox2(.png transparent)我想要的是使label1和pictrurebox2对pict​​urebox1透明，这样label1可以通过picturebox2看到但它无法正常工作..

 public Form1() { InitializeComponent(); label1.Parent = pictureBox1; label1.BackColor = Color.Transparent; pictureBox2.Parent = pictureBox1; pictureBox2.BackColor = Color.Transparent; picturebox2.BringToFront(); } 

所以请帮助我

Answer 1

如果需要控件支持透明度，则应覆盖控件的绘制并按以下顺序绘制控件：

• 在位图上的同一容器中绘制所有控件（基于z-index）。
• 然后在控件的图形上绘制该位图。
• 最后绘制控件的内容。
• 您的控件的BackColor也应该是Color.Transparent 。

这是创建TransparentLabel和TransparentPictureBox控件的结果。 在下面的图像中，有标签，图像，标签，图像，然后按顺序标签，如您所见，图片框和标签已呈现为具有透明背景并尊重z-index：

透明标签

 class TransparentLabel : Label { public TransparentLabel() { this.BackColor = Color.Transparent; } protected override void OnPaint(PaintEventArgs e) { if (Parent != null && this.BackColor == Color.Transparent) { using (var bmp = new Bitmap(Parent.Width, Parent.Height)) { Parent.Controls.Cast() .Where(c => Parent.Controls.GetChildIndex(c) > Parent.Controls.GetChildIndex(this)) .Where(c => c.Bounds.IntersectsWith(this.Bounds)) .OrderByDescending(c => Parent.Controls.GetChildIndex(c)) .ToList() .ForEach(c => c.DrawToBitmap(bmp, c.Bounds)); e.Graphics.DrawImage(bmp, -Left, -Top); } } base.OnPaint(e); } } 

透明PictureBox

 class TransparentPictureBox : PictureBox { public TransparentPictureBox() { this.BackColor = Color.Transparent; } protected override void OnPaint(PaintEventArgs e) { if (Parent != null && this.BackColor==Color.Transparent) { using (var bmp = new Bitmap(Parent.Width, Parent.Height)) { Parent.Controls.Cast() .Where(c => Parent.Controls.GetChildIndex(c) > Parent.Controls.GetChildIndex(this)) .Where(c => c.Bounds.IntersectsWith(this.Bounds)) .OrderByDescending(c => Parent.Controls.GetChildIndex(c)) .ToList() .ForEach(c => c.DrawToBitmap(bmp, c.Bounds)); e.Graphics.DrawImage(bmp, -Left, -Top); } } base.OnPaint(e); } }