/// <summary>
/// 验证 <see cref="MarkupExtension"/> 中此时提供的服务是否正在向 <see cref="FrameworkElement"/> 的依赖属性赋值。
/// </summary>
/// <param name="extension">需要进行通用验证的 <see cref="MarkupExtension"/>。</param>
/// <param name="serviceProvider">在 <see cref="MarkupExtension.ProvideValue"/> 方法中传入的参数。</param>
/// <param name="element">如果正在向 <see cref="FrameworkElement"/> 提供值，则返回此 <see cref="FrameworkElement"/> 实例。</param>
/// <returns>如果验证为此时可以赋值，则返回 true；如果因为设计时支持或者服务对象不存在，则返回 false。</returns>
internal static bool ValidateMarkupExtension(this MarkupExtension extension,
IServiceProvider serviceProvider, out FrameworkElement element)
{
if (extension == null)
{
throw new ArgumentNullException(nameof(extension));
}
if (serviceProvider == null)
{
throw new ArgumentNullException(nameof(serviceProvider));
}
var extensionName = extension.GetType().Name;
// 设计时直接创建新实例。
if (DesignerProperties.IsInDesignModeProperty.DefaultMetadata.DefaultValue is true)
{
element = null;
return(false);
}
// 如果没有服务，则直接返回。
if (!(serviceProvider.GetService(typeof(IProvideValueTarget)) is IProvideValueTarget service))
{
element = null;
return(false);
}
// MarkupExtension 在样式模板中，返回 this 以延迟提供值。
if (service.TargetObject.ToString().EndsWith("SharedDp", StringComparison.Ordinal))
{
throw new NotSupportedException($"样式和模板不支持 {extensionName}，请在 XAML 次根级元素中使用。");
}
if (service.TargetObject is SetterBase)
{
throw new NotSupportedException($"属性 Setter.Value 不支持 {extensionName}，请在 XAML 次根级元素中使用。");
}
if (!(service.TargetObject is FrameworkElement frameworkElement))
{
throw new NotSupportedException("只有 FrameworkElement 才能支持使用 ViewModel 设置 DataContext。");
}
element = frameworkElement;
return(true);
}
// Token: 0x060064CC RID: 25804 RVA: 0x001C4434 File Offset: 0x001C2634
internal static void CheckCanReceiveMarkupExtension(MarkupExtension markupExtension, IServiceProvider serviceProvider, out DependencyObject targetDependencyObject, out DependencyProperty targetDependencyProperty)
{
targetDependencyObject = null;
targetDependencyProperty = null;
IProvideValueTarget provideValueTarget = serviceProvider.GetService(typeof(IProvideValueTarget)) as IProvideValueTarget;
if (provideValueTarget == null)
{
return;
}
object targetObject = provideValueTarget.TargetObject;
if (targetObject == null)
{
return;
}
Type type = targetObject.GetType();
object targetProperty = provideValueTarget.TargetProperty;
if (targetProperty != null)
{
targetDependencyProperty = (targetProperty as DependencyProperty);
if (targetDependencyProperty != null)
{
targetDependencyObject = (targetObject as DependencyObject);
return;
}
MemberInfo memberInfo = targetProperty as MemberInfo;
if (memberInfo != null)
{
PropertyInfo propertyInfo = memberInfo as PropertyInfo;
EventHandler <XamlSetMarkupExtensionEventArgs> eventHandler = Helper.LookupSetMarkupExtensionHandler(type);
if (eventHandler != null && propertyInfo != null)
{
IXamlSchemaContextProvider xamlSchemaContextProvider = serviceProvider.GetService(typeof(IXamlSchemaContextProvider)) as IXamlSchemaContextProvider;
if (xamlSchemaContextProvider != null)
{
XamlSchemaContext schemaContext = xamlSchemaContextProvider.SchemaContext;
XamlType xamlType = schemaContext.GetXamlType(type);
if (xamlType != null)
{
XamlMember member = xamlType.GetMember(propertyInfo.Name);
if (member != null)
{
XamlSetMarkupExtensionEventArgs xamlSetMarkupExtensionEventArgs = new XamlSetMarkupExtensionEventArgs(member, markupExtension, serviceProvider);
eventHandler(targetObject, xamlSetMarkupExtensionEventArgs);
if (xamlSetMarkupExtensionEventArgs.Handled)
{
return;
}
}
}
}
}
Type type2;
if (propertyInfo != null)
{
type2 = propertyInfo.PropertyType;
}
else
{
MethodInfo methodInfo = (MethodInfo)memberInfo;
ParameterInfo[] parameters = methodInfo.GetParameters();
type2 = parameters[1].ParameterType;
}
if (!typeof(MarkupExtension).IsAssignableFrom(type2) || !type2.IsAssignableFrom(markupExtension.GetType()))
{
throw new System.Windows.Markup.XamlParseException(SR.Get("MarkupExtensionDynamicOrBindingOnClrProp", new object[]
{
markupExtension.GetType().Name,
memberInfo.Name,
type.Name
}));
}
}
else if (!typeof(BindingBase).IsAssignableFrom(markupExtension.GetType()) || !typeof(Collection <BindingBase>).IsAssignableFrom(targetProperty.GetType()))
{
throw new System.Windows.Markup.XamlParseException(SR.Get("MarkupExtensionDynamicOrBindingInCollection", new object[]
{
markupExtension.GetType().Name,
targetProperty.GetType().Name
}));
}
}
else if (!typeof(BindingBase).IsAssignableFrom(markupExtension.GetType()) || !typeof(Collection <BindingBase>).IsAssignableFrom(type))
{
throw new System.Windows.Markup.XamlParseException(SR.Get("MarkupExtensionDynamicOrBindingInCollection", new object[]
{
markupExtension.GetType().Name,
type.Name
}));
}
}
public override object CallProvideValue(MarkupExtension me, IServiceProvider serviceProvider)
{
object obj3;
try
{
obj3 = me.ProvideValue(serviceProvider);
}
catch (Exception exception)
{
if (CriticalExceptions.IsCriticalException(exception))
{
throw;
}
throw this.CreateException(System.Xaml.SR.Get("ProvideValue", new object[] { me.GetType() }), exception);
}
return(obj3);
}
internal static void CheckCanReceiveMarkupExtension(MarkupExtension markupExtension, IServiceProvider serviceProvider, out DependencyObject targetDependencyObject, out DependencyProperty targetDependencyProperty)
{
targetDependencyObject = null;
targetDependencyProperty = null;
var provideValueTarget = serviceProvider.GetService(typeof(IProvideValueTarget)) as IProvideValueTarget;
if (provideValueTarget == null)
{
return;
}
var targetObject = provideValueTarget.TargetObject;
if (targetObject == null)
{
return;
}
var type = targetObject.GetType();
var targetProperty = provideValueTarget.TargetProperty;
if (targetProperty != null)
{
targetDependencyProperty = targetProperty as DependencyProperty;
if (targetDependencyProperty != null)
{
targetDependencyObject = targetObject as DependencyObject;
}
else
{
var memberInfo = targetProperty as MemberInfo;
if (memberInfo != null)
{
var propertyInfo = memberInfo as PropertyInfo;
EventHandler <XamlSetMarkupExtensionEventArgs> eventHandler = LookupSetMarkupExtensionHandler(type);
if (eventHandler != null && propertyInfo != null)
{
var schemaContextProvider = serviceProvider.GetService(typeof(IXamlSchemaContextProvider)) as IXamlSchemaContextProvider;
if (schemaContextProvider != null)
{
var xamlType = schemaContextProvider.SchemaContext.GetXamlType(type);
if (xamlType != null)
{
var member = xamlType.GetMember(propertyInfo.Name);
if (member != null)
{
var e = new XamlSetMarkupExtensionEventArgs(member, markupExtension, serviceProvider);
eventHandler(targetObject, e);
if (e.Handled)
{
return;
}
}
}
}
}
var c = !(propertyInfo != null) ? ((MethodBase)memberInfo).GetParameters()[1].ParameterType : propertyInfo.PropertyType;
if (!typeof(MarkupExtension).IsAssignableFrom(c) || !c.IsAssignableFrom(markupExtension.GetType()))
{
throw new System.Windows.Markup.XamlParseException(__SR.Get("MarkupExtensionDynamicOrBindingOnClrProp",
markupExtension.GetType().Name, memberInfo.Name, type.Name));
}
}
else if (!typeof(BindingBase).IsAssignableFrom(markupExtension.GetType()) || !typeof(Collection <BindingBase>).IsAssignableFrom(targetProperty.GetType()))
{
throw new System.Windows.Markup.XamlParseException(__SR.Get("MarkupExtensionDynamicOrBindingInCollection",
markupExtension.GetType().Name, targetProperty.GetType().Name));
}
}
}
else if (!typeof(BindingBase).IsAssignableFrom(markupExtension.GetType()) || !typeof(Collection <BindingBase>).IsAssignableFrom(type))
{
throw new System.Windows.Markup.XamlParseException(__SR.Get("MarkupExtensionDynamicOrBindingInCollection",
markupExtension.GetType().Name, type.Name));
}
}