通过反射查找给定/动态类型的ObservableCollection [英] Finding an ObservableCollection for given/dynamic type via reflection

问题描述

我有一个带有几个ObservableCollections的Class，用于不同类型.现在，我想通过反射找到给定类型的正确Collection，因为我不想构建一个if-monster，每次添加另一个Collection时都必须对其进行更新.

I have a Class with several ObservableCollections for different types. Now, I want to find the correct Collection for a given type via reflection, because I don't want to build an if-monster which I have to update every time I add another Collection.

此方法是第一步:

public ObservableCollection<T> GetObservableCollectionForType<T>()
{

   foreach (PropertyInfo info in this.GetType().GetProperties())
   {

      if (info.GetGetMethod() != null && info.PropertyType == typeof(ObservableCollection<T>))
         return (ObservableCollection<T>)this.GetType().GetProperty(info.Name).GetValue(this, null);                   

   }

   return null;

}

现在，我需要第二种方法，该方法接受一个具体对象作为参数并找到正确的Collection.像这样:

Now, I need a second method, which accepts a concrete object as parameter and finds the correct Collection. Somehow like this:

public ObservableCollection<T> GetObservableCollectionFor(object sObject)
{

   Type wantedType = sObject.GetType();

   foreach (PropertyInfo info in this.GetType().GetProperties())
   {

     if (info.GetGetMethod() != null && info.PropertyType == ObservableCollection<wantedType>)
        return this.GetType().GetProperty(info.Name).GetValue(this, null);

   }

   return null;

}

有什么想法可以实现这一目标吗?

Any ideas how to realize this?

更新:

可行的解决方案:

public object GetObservableCollectionFor(object sObject)
{

   Type wantedType = sObject.GetType();

   foreach (PropertyInfo info in this.GetType().GetProperties())
   {

      if (info.GetGetMethod() != null && info.PropertyType == typeof(ObservableCollection<>).MakeGenericType(new[]{wantedType}))
         return this.GetType().GetProperty(info.Name).GetValue(this, null);

   }

   return null;

}

这将返回正确的集合作为对象.我仍然不知道如何转换为正确的泛型类型，但是转换为IList就足以添加和删除.

This will return the correct collection as object. I still don't know how to cast to the correct generic type, but casting to IList is enough for adding and removing.

推荐答案

比较属性的类型时，您似乎需要在ObservableCollection类型上添加对MakeGenericType()的调用.还没有测试过，但也许...

When comparing the type of the property, it looks like you need to add a call to MakeGenericType() on the ObservableCollection type. Haven't tested this but maybe something like...

public ObservableCollection<T> GetObservableCollectionFor(object sObject)
{

   Type wantedType = sObject.GetType();

   foreach (PropertyInfo info in this.GetType().GetProperties())
   {

     if (info.GetGetMethod() != null && info.PropertyType == typeof(ObservableCollection<>).MakeGenericType(new[]{Type.GetType(wantedType)})

        return (ObservableCollection<T>)this.GetType().GetProperty(info.Name).GetValue(this, null);

   }

   return null;

}

修改 为避免使用值类型进行间接装箱，可以通过将参数类型从对象更改为类型T来改进上述方法定义.

Edit To avoid overhead boxing with value types, the above method definition could be improved by changing the parameter type from object to type T

public ObservableCollection<T> GetObservableCollectionFor(T sObject)

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