Difference between using the append method of the StringBulder class and the concatenation operator "+"

Question

What is the difference in using the Append method of the StringBuilder and Concatenation classes with the "+" operator?

How does the Append method work more efficiently or faster than the + operator in concatenating two strings?

Answer 1

First of all, Stringand StringBuilder- different classes.

Stringa class represents immutable types , but a class StringBuilderrepresents mutable types.

When you use +to combine your lines, it uses String.Concat. And each time it returns a new string object.

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1: Simple Concatenation 606 ms
2: String.Format    665 ms
3: string.Concat    587 ms
4: String.Replace   979 ms
5: StringBuilder    588 ms

Answer 2

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Answer 3

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string s = "a" + "b";

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