This has probably been done a hundred times already, but I couldn't find one in the first few pages of google results, so I wrote my own in ~40 lines of C#:

using System;
using System.ComponentModel;
using System.Drawing;
using System.Drawing.Drawing2D;
using System.Windows.Forms;

namespace PostXING.Controls
{
/// <summary>
/// GradientPanel is just like a regular panel except it optionally
/// shows a gradient.
/// </summary>
[ToolboxBitmap(typeof(Panel))]
public class GradientPanel : Panel
{
/// <summary>
/// Property GradientColor (Color)
/// </summary>
private Color _gradientColor;
public Color GradientColor {
get { return this._gradientColor;}
set { this._gradientColor = value;}
}

/// <summary>
/// Property Rotation (float)
/// </summary>
private float _rotation;
public float Rotation {
get { return this._rotation;}
set { this._rotation = value;}
}

protected override void OnPaint(PaintEventArgs e) {
if(e.ClipRectangle.IsEmpty) return; //why draw if non-visible?


using(LinearGradientBrush lgb = new
LinearGradientBrush(this.ClientRectangle,
this.BackColor,
this.GradientColor,
this.Rotation)){
e.Graphics.FillRectangle(lgb, this.ClientRectangle);
}

base.OnPaint (e); //right, want anything handled to be drawn too. } } }

There it is. Enjoy!

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