如何向 IGrouping 添加扩展方法？

Question

I created method like this:

private TProperty CheckElements<TElement, TProperty>(IGrouping<string, TElement> group, Func<TElement, TProperty> propertySelector) 

and i invoke it like this inside Select done after GroupBy (gr is IGrouping inside select):

val = CheckElements(gr, x => x.SomeProperty)

How can i extend IGrouping? So that i can just:

val = gr.CheckElements(x => x.SomeProperty)

Answer 1

Try something like this:

  static class Extension
{
    public static TProperty CheckElements<TElement, TProperty>(this IGrouping<string, TElement> group,
        Func<TElement, TProperty> propertySelector)
    {
      ...
    }

 
}