1.Add resource dictionary,Brushes.xaml
<ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
<LinearGradientBrush EndPoint="1,0" x:Key="brush1">
<GradientStop Color="Yellow" Offset="0"/>
<GradientStop Color="Orange" Offset="0.7"/>
<GradientStop Color="DarkRed" Offset="1"/>
</LinearGradientBrush>
</ResourceDictionary>
2.In App.xaml
<Application x:Class="WpfApp186.App"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:local="clr-namespace:WpfApp186"
StartupUri="MainWindow.xaml">
<Application.Resources>
<ResourceDictionary>
<ResourceDictionary.MergedDictionaries>
<ResourceDictionary Source="Brushes.xaml"/>
</ResourceDictionary.MergedDictionaries>
</ResourceDictionary>
</Application.Resources>
</Application>
3.MainWindow.xaml
<Window x:Class="WpfApp186.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:local="clr-namespace:WpfApp186"
mc:Ignorable="d" WindowState="Maximized"
Title="MainWindow" Height="450" Width="800">
<Grid>
<Ellipse Fill="{StaticResource brush1}"/>
</Grid>
</Window>
标签：resource,dictionary,ResourceDictionary,WPF,MergedDictionaries,xaml From： https://www.cnblogs.com/Fred1987/p/18278903