List.Exists(Predicate match)

Hi,

At times when you want to check for an Item inside a List list, you can use the Exists method as follows.

List.Exists(Predicate match)

List l = new List();
l.Add("Red");
l.Add("Green");
l.Add("Blue");
l.Add("Purple");

//prints "true" as "Red" is in the list
Console.WriteLine(l.Exists(delegate(string s) { return s == "Red"; }));

//prnts "false" as "Pink" is not in the list
Console.WriteLine(l.Exists(delegate(string s) { return s == "Pink"; }));
Published 30 September 04 08:00 by BradA
http://blogs.msdn.com/brada/archive/2004/09/30/236460.aspx

In my case I had to check against an object and not the string.

this will work, SourceFieldID is of type string.
bool itemExists = _criteriaItems.Items.Exists(delegate(CriteriaItem ci) { return ci.SourceFieldId == item.SourceFieldId; });

but this wont work, it will always return false.
bool itemExists = _criteriaItems.Items.Exists(delegate(CriteriaItem ci) { return ci == item; });

happy coding!!

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