string concat in c#?

what is different between string +, 开发者_开发技巧string.concat();

i mean

string a="sasi", string b="surya";

string x= a+b, and string x= string.concat(a,b);

In that case, nothing, really. However, string.Concat() can also be used to:

• Concatenate an array of strings (string.Concat(string[]))
• Concatenate the string representations of an array of objects (string.Concat(object[]))
• Concatenate an IEnumerable<T> of strings

See here for the full overload list.

There is no difference. The plus (+) operator compiles to a string.concat method; see here and here.

Newer versions of the compiler optimize the usage of the (+) operator anyways, so they are equally efficient.

If you want to see a performance benchmark check this post from Jeff

Concat performs 1 concatination regardless of how many strings are provided so has better performance over the + operaton. http://www.interact-sw.co.uk/iangblog/2004/03/16/concatperf