SHJX_GM/SHJX.Service.WorkFlowEdit/themes/DiagramView.xaml

<ResourceDictionary
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:d="clr-namespace:SHJX.Service.WorkFlowEdit">

    <ResourceDictionary.MergedDictionaries>
        <ResourceDictionary Source="/SHJX.Service.WorkFlowEdit;component/Themes/Shared.xaml" />
    </ResourceDictionary.MergedDictionaries>

    <Style TargetType="{x:Type d:DiagramView}">
        <Setter Property="SnapsToDevicePixels" Value="True" />
        <Setter Property="Background" Value="White" />
    </Style>

</ResourceDictionary>