New to use of Drawing Class....

I'm trying to create an asp.net page/control that will display a green
to yellow to red gradient bar.

Not seeing where I could create a 3 color gradient, I create a green
to yellow rectangle and then a yellow to red rectangle and join them
in one bitmap.

The code below works but has a red line where my two gradient brushes
meet.

I played with the width x and width settings but the line remained.

Thoughts?

Thanks in advance


using System.Drawing;
using System.Drawing.Drawing2D;
using System.Drawing.Imaging;

private void Page_Load(object sender, System.EventArgs e)
{
	// Put user code to initialize the page here




	Bmp = new Bitmap(150,10);

	Gfx = Graphics.FromImage(Bmp);

	LinearGradientBrush brGY=new LinearGradientBrush(
		new Rectangle(0,0,75,10),
		Color.Green,
		Color.Yellow,
		0,
		false);

	LinearGradientBrush brYR=new LinearGradientBrush(
		new Rectangle(75,0,75,10),
		Color.Yellow,
		Color.Red,
		0,
		false);

	Gfx.FillRectangle(brGY,new Rectangle(0,0,75,10));
	Gfx.FillRectangle(brYR,new Rectangle(75,0,75,10));

	Bmp.Save(Response.OutputStream, ImageFormat.Jpeg);


}

You can create gradients with multiple colours using a ColorBlend see 
the Beginners Guide to GDI+ from my web-site for an example.

http://www.bobpowell.net/linear.htm

-- 
Bob Powell [MVP]
Visual C#, System.Drawing

Ramuseco Limited .NET consulting
http://www.ramuseco.com

Find great Windows Forms articles in Windows Forms Tips and Tricks
http://www.bobpowell.net/tipstricks.htm

Answer those GDI+ questions with the GDI+ FAQ
http://www.bobpowell.net/faqmain.htm

All new articles provide code in C# and VB.NET.
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TD wrote:

> New to use of Drawing Class....
> 
> I'm trying to create an asp.net page/control that will display a green
> to yellow to red gradient bar.
> 
> Not seeing where I could create a 3 color gradient, I create a green
> to yellow rectangle and then a yellow to red rectangle and join them
> in one bitmap.
> 
> The code below works but has a red line where my two gradient brushes
> meet.
> 
> I played with the width x and width settings but the line remained.
> 
> Thoughts?
> 
> Thanks in advance
> 
> 
> using System.Drawing;
> using System.Drawing.Drawing2D;
> using System.Drawing.Imaging;
> 
> private void Page_Load(object sender, System.EventArgs e)
> {
> 	// Put user code to initialize the page here
> 
> 
> 
> 
> 	Bmp = new Bitmap(150,10);
> 
> 	Gfx = Graphics.FromImage(Bmp);
> 
> 	LinearGradientBrush brGY=new LinearGradientBrush(
> 		new Rectangle(0,0,75,10),
> 		Color.Green,
> 		Color.Yellow,
> 		0,
> 		false);
> 
> 	LinearGradientBrush brYR=new LinearGradientBrush(
> 		new Rectangle(75,0,75,10),
> 		Color.Yellow,
> 		Color.Red,
> 		0,
> 		false);
> 
> 	Gfx.FillRectangle(brGY,new Rectangle(0,0,75,10));
> 	Gfx.FillRectangle(brYR,new Rectangle(75,0,75,10));
> 
> 	Bmp.Save(Response.OutputStream, ImageFormat.Jpeg);
> 
> 
> }
>