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Problem with Dictionary<T,U>.Keys enumerator returning invalid keys

I'm experiencing some wierd behavior with a Dictionary<T,U> class using
foreach loops, such that the Key returned in the foreach is not contained in
the dictionary.

code:

Dictionary<A, B> dict;
.....
foreach(A key in dict.Keys)
{
bool foo = dict.ContainsKey(A); //returning false
}

Does anyone know what kinds of circumstances could cause this?

Jun 5 '06 #1
1 1297
"Brian Richards" <br*******@gmail.com> wrote:
I'm experiencing some wierd behavior with a Dictionary<T,U> class using
foreach loops, such that the Key returned in the foreach is not contained in
the dictionary.

code:

Dictionary<A, B> dict;
....
foreach(A key in dict.Keys)
{
bool foo = dict.ContainsKey(A); //returning false
}

Does anyone know what kinds of circumstances could cause this?


What type is A? Has it had its Equals() and GetHashCode() methods
overridden? If so, are the instances mutable after they have been
constructed? If so, have they been modified after adding to the
dictionary?

-- Barry

--
http://barrkel.blogspot.com/
Jun 5 '06 #2

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