Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Welcome To Ask or Share your Answers For Others

Categories

0 votes
368 views
in Technique[技术] by (71.8m points)

c# - Draw a Fill Rectangle with low opacity

I a have a PictureBox with a picture in a Windows Form application in C# language.I want draw a FillRectangle in some location of picturebox.but i also need to see picture of picture box.how can i draw this rectangle with low opacity to see image of picturebox?

See Question&Answers more detail:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Reply

0 votes
by (71.8m points)

Do you mean:

using (Graphics g = Graphics.FromImage(pb.Image))
{
    using(Brush brush = new SolidBrush(your_color))
    {
        g.FillRectangle(brush , x, y, width, height);
    }
}

or you can use

Brush brush = new SolidBrush(Color.FromArgb(alpha, red, green, blue))

where alpha goes from 0 to 255, so a value of 128 for your alpha will give you 50% opactity.


与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
OGeek|极客中国-欢迎来到极客的世界,一个免费开放的程序员编程交流平台!开放,进步,分享!让技术改变生活,让极客改变未来! Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Click Here to Ask a Question

...