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c#ilistsortedlistfindall

How do I perform a FindAll() on an IList<T>? (eg. SortedList.Values)

I'm working on a problem in C# 2.0/.NET 2.0 where I have a Sortedlist and want to search all the "values" (not the "keys") of this SortedList for a certain substring and count up how many occurrences there are.

This is what I'm trying to do:

{
   Sortedlist<string,string> mySortedList;
   // some code that instantiates mySortedList and populates it with data
   List<string> myValues = mySortedList.Values;  // <== does not work
   int namesFound = myValues.FindAll(ByName(someName)).Count;
}

Naturally, this doesn't work because mySortedList.Values returns an IList, while "myValues" is a List. I tried "casting" the IList so that it would be accepted by myValues, but it doesn't seem to work.

Of course, I can loop over mySortedList.Values in a "foreach" loop, but I don't really want to do this.

Anyone have any suggestions?

EDIT-1: Ok, well it looks like there isn't a native way to do this easily. I had assumed that I was just missing something, but apparently I'm not. So I guess I'm just going to do a "foreach" over the IList.

Thanks for the feedback everyone! I voted everyone up 1 because I thought all the feedback was good. Thanks again! :-)

EDIT-2: Looks like CMS has the answer I was looking for. The only caveat with this (as Qwertie pointed out) is that there is a potential performance penalty since it involves copying all the values to another List and then searching that list start-to-finish. So for short lists, this answer is effective. Longer lists? well that's up to you to decide...

Solution

  • Since the IList Interface implements IEnumerable, you can actually get a List<T> of values using the List<T> (IEnumerable) Constructor:

    List<string> myValues = new List<string>(mySortedList.Values);