How to fix UTF encoding for whitespaces?
194 160 is the UTF-8 encoding of a NO-BREAK SPACE codepoint (the same codepoint that HTML calls ).
So it's really not a space, even though it looks like one. (You'll see it won't word-wrap, for instance.) A regular expression match for \s would match it, but a plain comparison with a space won't.
To simply replace NO-BREAK spaces you can do the following:
src = src.Replace('\u00A0', ' ');
奇怪的字符，看起來像是空格，實際上又不是空格
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