wpf 根据数据应用静态资源

Question

如何根据数据按名称应用静态资源？我知道我可以为样式属性编写数据触发器，但我想根据绑定(bind)数据应用整个样式。

前任:
if (条件) CellValuePresenterStyle="{StaticResource OptionalFieldCellPresenter}"
否则 CellValuePresenterStyle="{StaticResource RequiredFieldCellPresenter}"

Answer 1

您可以编写一个自定义转换器来处理这个问题。 Converter 类如下所示:

//''' <summary>
//''' Returns a Style  based upon the text that is passed into the Convert
//''' function in the 'value' object.
//''' </summary>
//''' <remarks></remarks>
Public Class NameToStyleConverter
   Implements IValueConverter

   Public Function Convert(ByVal value As Object, ByVal targetType As System.Type, ByVal parameter As Object, ByVal culture As System.Globalization.CultureInfo) As Object Implements System.Windows.Data.IValueConverter.Convert
      Dim styleName As String = CStr(value)
      Dim styl As System.Windows.Style

      styl = Application.Current.TryFindResource(styleName)

      Return styl

   End Function

   Public Function ConvertBack(ByVal value As Object, ByVal targetType As System.Type, ByVal parameter As Object, ByVal culture As System.Globalization.CultureInfo) As Object Implements System.Windows.Data.IValueConverter.ConvertBack
      Throw New NotImplementedException("This method or operation is not implemented.")
   End Function
End Class

在您的窗口的 XAML 中，您将拥有以下内容:

<Window.Resources>
    <local:NameToStyleConverter x:Key="NameToStyleConverter"/>
</Window.Resources>

其中 'local' 是为您的应用程序定义的命名空间。

实现可能如下所示:

Style="{Binding Path=MyStyleNameText, Converter={StaticResource NameToStyleConverter}"

或者，您可以随时从代码中引用转换器。你传入一个字符串，它会返回一个样式。