C# 6 and the nameof(x) operator

In C# 6 the new operator nameof was introduced. It helps the developer to use any property/classname/namespace and so on as a string. The string will be set at compile time.
Lets start with some examples.:
When checking arguments before C# 6 you had to use the following to output the argument name which was not set or had an invalid value.
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With the new nameof operator you can use this:
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The nameof operator will be executed at compile time. This is how the above code looks in IL Spy:
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As we can see, the compiler inserted for nameof(args) “args”.
It doesn’t look like a revolution, but for me it is a very handy feature.

Everytime you need the name of a property/class or a namespace you can use nameof().

This also allows you to use this for enums.
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Before nameof() you had to use the .ToString() method with costs processing time. Now you can just use the new C# feature and the value gets evaluated at compile time. Here is the difference in IL Spy:
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The result of nameof(MyEnum.Value0) gets directly written to the IL code.


Posted Dec 01 2015, 03:49 PM by Holger Vetter
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