ruby - 任何人都知道字符串开头的 "weird"字符是怎么回事？

Question

我在尝试从它们的数组中检测某个字符串时遇到了一个奇怪的问题。有人知道这里发生了什么吗？

(rdb:1) p magic_string
"Time Period"
(rdb:1) p magic_string.class
String
(rdb:1) p magic_string == "Time Period"
false
(rdb:1) p "Time Period".length
11
(rdb:1) p magic_string.length
14
(rdb:1) p magic_string[0].chr
"\357"
(rdb:1) p magic_string[1].chr
"\273"
(rdb:1) p magic_string[2].chr
"\277"
(rdb:1) p magic_string[3].chr
"T"

Answer 1

您的字符串开头包含 3 个字节 (BOM)，表示编码为 UTF-8。

Q: What is a BOM?

A: A byte order mark (BOM) consists of the character code U+FEFF at the beginning of a data stream, where it can be used as a signature defining the byte order and encoding form, primarily of unmarked plaintext files. Under some higher level protocols, use of a BOM may be mandatory (or prohibited) in the Unicode data stream defined in that protocol.

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