Compare strings, equals air defense pointer issues

Source: Internet
Author: User

1, compare two string content, compare with a.equals (b), where a, B is two strings, compared with the a==b words is the memory address.
2, if a string is a variable, and the other string is a constant, be sure to write the constant in front, the variable is written in the back (that is, in parentheses), so that only one reason to avoid the exception of the report null pointer. Such as: A is a constant string, B is a variable string, it must be written as A.equals (b). cannot be written as B.equals (a), otherwise if B is null, the null pointer exception is absolute.

Novice all need to pay attention to these two points ah.

I hope I can help you.

Compare strings, equals air defense pointer issues

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