pros and cons of using the struct or class for string

Question

Possible Duplicate:
What is the difference between String and string

I have two scenarios where both a Struct and Class are acceptable, and I'm wondering what is the best practice.

Scenario 1:

public static String foo(){...}//String is a class

public static string foo(){...}//string is a struct

Scenario 2:

public foo(String bar){...}//String is a class

public foo(string bar){...}//string is a struct

What are the pros/cons to each implementation?

`string` is not a struct. It's an alias for the class `System.String`. — user703016, Aug 30 '12 at 14:09
`string` is a C# alias for `System.String` which is a class. It is not a struct. — gideon, Aug 30 '12 at 14:09
Actually, there is a significant difference for the compiler (not very significant, but significant nonetheless). If you use the upper-case `String`, the compiler has to resolve it in the context of your `using` statements, to see whether you indeed meant `System.String` or perhaps `AdvancedPhysics.String` or `RememberToBuyButter.TieAroundFinger.String`. Lower-case `string`, on the other hand, is a keyword, and can only ever refer to `System.String`. — phoog, Aug 30 '12 at 14:19

score 5 · Answer 1 · edited May 23 '17 at 10:34

5

The implementations are the same. String is a class, string is just alias.

For details see the following answer: What is the difference between String and string in C#?

edited May 23 '17 at 10:34

Community

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answered Aug 30 '12 at 14:08

Artem Vyshniakov

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phoog's comment makes this technically incorrect, but unless the OP is using a theoretical physics library it's extremely unlikely for String to be anything other than System.String, so it's correct in the most likely case. – KeithS Aug 30 '12 at 14:23
@KeithS nor for that matter, is it that likely that someone who could code a worthwhile theoretical physics library not spotting the downside of naming any .NET class `String`, at some point before they shipped. – Jon Hanna Aug 30 '12 at 14:35
Who knows, those string theorists are a loopy bunch (or so CBS tells me :P ). I seem to remember an episode where our heroes are trying to build a smartphone app, and have to kick Sheldon out of the development effort (mostly for being such a micromanager/ivory-tower type, but still). – KeithS Aug 30 '12 at 14:40

David Hoerster · Answer 2 · 2012-08-30T14:15:54.950

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String and string are the same thing. They're both reference types, which means they are classes (little 's' string is an alias to the real class String).

I personally prefer using the class names instead of the aliases in my code. I guess I prefer the consistency between declaring variables of a certain type and then using static methods off those types (like String.Format).

edited Aug 30 '12 at 14:15

answered Aug 30 '12 at 14:09

David Hoerster

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Thanks @Cicada - guess I typed that too fast. It made sense to me. :) – David Hoerster Aug 30 '12 at 14:13
What's static methods got to do with anything? You could argue just as well for `string.Format` than for `String.Format`. – Jon Hanna Aug 30 '12 at 14:36

score 0 · Answer 3 · answered Aug 30 '12 at 14:09

0

string is just an alias of String Type, the code MSIL is same

answered Aug 30 '12 at 14:09

Aghilas Yakoub

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score 0 · Answer 4 · answered Aug 30 '12 at 14:11

0

String and string is same such as Int32 and int.

answered Aug 30 '12 at 14:11

Kirill Bestemyanov

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pros and cons of using the struct or class for string

4 Answers4