How do I draw a rectangle onto an image with transparency and text

c#, gdi+

Solution

You can try something like this:

// Load the image (probably from your stream)
Image image = Image.FromFile( imagePath );

using (Graphics g = Graphics.FromImage(image))
{
   // Modify the image using g here... 
   // Create a brush with an alpha value and use the g.FillRectangle function
}

image.Save( imageNewPath );

Edit: the code to create a semi transparency gray brush

Color customColor = Color.FromArgb(50, Color.Gray);
SolidBrush shadowBrush = new SolidBrush(customColor);
g.FillRectangles(shadowBrush, new RectangleF[]{rectFToFill});

Problem

This is my first graphics based project and to begin with I need to be able to draw a rectangle onto a bitmap with transparency and text. I'm not sure where to begin with this. I've done a little research but can't seem to find an article that will allow me to add a semi transparent rectangle to an image. What I will have is an image stream that I need to be able to manipulate. Can someone please point me in the right direction for this? A site with source would be great as I have never done any GDI work before.

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