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Hashtable

I know how to get Hashtable value by key, but How can I get Hashtable key by
it's value?
Nov 16 '05 #1
3 2343
You would have to manually search the table for that value.
You could enumerate the table to look for the value, for instance:

Hashtable ht...;
object value...;
IDictionaryEnumerator de = ht.GetEnumerator();
while (de.MoveNext())
{
if (value == de.Value)
Console.WriteLine(de.Key);
}

--
Regards,
Dennis JD Myrén
Oslo Kodebureau
"Dave" <da*********@hotmail.com> wrote in message
news:%2****************@TK2MSFTNGP14.phx.gbl...
I know how to get Hashtable value by key, but How can I get Hashtable key
by it's value?

Nov 16 '05 #2
Dave <da*********@hotmail.com> wrote:
I know how to get Hashtable value by key, but How can I get Hashtable key by
it's value?


You can do it by brute force as Dennis said, but if you're going to
have to do this regularly, you should have two Hashtables - one to map
one way, and the other to map the other way.

--
Jon Skeet - <sk***@pobox.com>
http://www.pobox.com/~skeet
If replying to the group, please do not mail me too
Nov 16 '05 #3
Note, also, that while the key is guaranteed to be unique (points to
just one value), the value is not -- several keys could have the same value.

--
Truth,
James Curran
[erstwhile VC++ MVP]
Home: www.noveltheory.com Work: www.njtheater.com
Blog: www.honestillusion.com Day Job: www.partsearch.com

"Dave" <da*********@hotmail.com> wrote in message
news:%2****************@TK2MSFTNGP14.phx.gbl...
I know how to get Hashtable value by key, but How can I get Hashtable key by it's value?

Nov 16 '05 #4

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