问题
i have seen [] such brackets in c# very very rarely but when i start to learn asp.net i have seen them many times but still i couldn't understand what they does ?
They are not part of code as using for arrays.For example [webmethods] which is just over the methods or there are some over classes. Are they part of .net or they are just tell something to CLR ? or ?
回答1:
They are used to put Attributes on classes or methods (or other stuff). That way, you can attach data to classes that should not be part of the actual class. You can read more on them here
回答2:
You're seeing .Net attributes, which can annotate types and members.
回答3:
[] brackets are an operator in C#. The link contains more detailed information and examples of what I summarized below.
They are used for:
- Array type definition
- Access an element of an array
- They can be used as indexer parameters for any type
- They can be used to specify attributes <-- This seems like what you are asking about
- They can be used for unsafe code to index an offset from a pointer
回答4:
They're attributes used to annotate methods and classes.
回答5:
It is an operator which is most commonly used for indexing into some sort of collection. The common use is for indexing into an array.
They are also commonly used in C# to define attributes. These can appear above methods and classes. They are a way of defining extra behavior for that class or method.
MSDN has a good Introduction to Attributes in C#.
回答6:
They are attributes, posting from my phone so I can't add links but just search msdn for attributes.
回答7:
As some other said, they are attributes, you should really check MSDN about them, but in short, you could say they add code that can can be executed before or after the method is executed, or not at all! They do many different things, from being conditionals to decide if the method should run or not, to do a preprocessing operation, to just adding MetaData to the code, so other libraries or the compiler can find it and do stuff with it.
来源：https://stackoverflow.com/questions/2968597/what-is-brackets-in-net