Stroke with horizontal multi-color LinearGradientBrush
<Window x:Class="WpfApplication1.Window1" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" Title="WPF" Height="300" Width="300"> <Canvas Margin="5"> <!--Stroke with horizontal multi-color LinearGradientBrush--> <Line X1="20" X2="280" Y1="240" Y2="240" StrokeThickness="30"> <Line.Stroke> <LinearGradientBrush StartPoint="0,0.5" EndPoint="1,0.5"> <GradientStop Color="Red" Offset="0.15" /> <GradientStop Color="Orange" Offset="0.2" /> <GradientStop Color="Yellow" Offset="0.35" /> <GradientStop Color="Green" Offset="0.5" /> <GradientStop Color="Blue" Offset="0.65" /> <GradientStop Color="Indigo" Offset="0.75" /> <GradientStop Color="Violet" Offset="0.9" /> </LinearGradientBrush> </Line.Stroke> </Line> </Canvas> </Window>