问题
I am coding a simple program using a scanner and now want to make sure the user only types "yes" or "no" by comparing the input to these words. I'm using a normal if-statement with || (pipes):
if (!input.equals("yes") || !input.equals("no")) {
//do something
}
Java (I am using BlueJ) complains about my pipes, it says: "illegal character: '\u00a0'"
What I tried
- I copied & pasted pipes from the wikipedia site to make sure I am really using correct pipe-characters
- restarted BlueJ
- tried using equal signs (&&), same error
- if I removed the second condition and the pipes it works
Does anyone have an idea why it complains and how I can fix it? – Thanks in advance
回答1:
The character u00a0 is a non-breaking space.
It seems like you typed a control char in your code, replace everything from a copy of this line
if(!input.equals("yes") && !input.equals("no"))
Or simply suppress the spaces in your line and re-type them (making sure you don't type in nbsp).
Notice that I changed the || to && as typing "no" for example would still enter the condition as "yes" would not equals to input. Your condition would then be true || false which would result in true.
In any case, this is not related to the || or && operator, it is the spaces.
回答2:
'\u00a0'parses to a non breaking space, so maybe it's not the pipes that are the problem. try eliminating the space around the pipes and enclosing the negated statements in parentheses and see if the error persists.
来源：https://stackoverflow.com/questions/29496347/java-or-and-characters-illegal-in-if-statement