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ElementName
The ElementName property is used to reference an object by the name of the object. This is particularly useful in XAML, where you can directly reference other elements defined in XAML.
举例
<StackPanel Background=”Blue”>
<Button x:Name=”refButton” Background=”Orange”/>
<Button Background=”{Binding ElementName=refButton, Path=Background}”/>
</StackPanel>
Source
The Source property is used to specify an object reference on which the binding Path or XPath will be evaluated. The Source property is usually used when the object on which the Binding is set is known and differs from the DataContext.
举例:
<CustomClass1 Property1=”{Binding Source={x:Static DateTime.Now}, Path=Day}”/>
<CustomClass1 Property1=”{Binding Source={StaticResource AnotherElement}, Path=ActualWidth}”/>
简单地说，“ElementName”用于绑定到xaml界面设计中添加的其它控件对象，“Source”用于绑到资源中的对象。