How can an object not be compared to null?

Posted by ProfK on Stack Overflow See other posts from Stack Overflow or by ProfK
Published on 2009-03-15T16:48:45Z Indexed on 2010/04/12 3:23 UTC
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.NET

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generics

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c#

I have an 'optional' parameter on a method that is a KeyValuePair. I wanted an overload that passes null to the core method for this parameter, but in the core method, when I want to check if the KeyValuePair is null, I get the following error:

Operator '!=' cannot be applied to operands of type System.Collections.Generic.KeyValuePair<string,object>' and '<null>.

How can I not be allowed to check if an object is null?

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