Re: List<>.Exists()???


"Marc Gravell" <marc.gravell@xxxxxxxxx> wrote in message
news:O3nwLkkNIHA.3940@xxxxxxxxxxxxxxxxxxxxxxx
What you are looking for is List<T>.Contains(...), i.e.



This answer has come up before...

I think it may have something to do with the fact that the help article for
Exists doesn't mention Contains anywhere, never mind as a "Remarks: To find
whether the list contains an element equal to a provided element, use the
Contains method".

if(!numList.Contains(newNumber)) {...}

That should fix it; for completeness:
List<T>.Exists(...) checks whether any of the items in the list satisfies
a condition (specified as a predicate); for example, to test whether any
of the numbers are divisible by 3 (using the new C# 3 "lambda" syntax):

if (numList.Exists(i => i % 3 == 0)) {...}

The "predicate" is just a method that accepts the item to be tested and
returns true (match) or false:

static bool SomeMethod(int i) {
return i % 3 == 0;
}
...
if (numList.Exists(SomeMethod)) {...}

Does that make it any clearer?

Marc



.

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