使用 `?`(问号)在 Ruby 中获取 ASCII 字符代码失败 [英] Getting an ASCII character code in Ruby using `?` (question mark) fails

问题描述

我需要一个字符的 ASCII 值(对于 Project Euler 问题 #22，如果你想具体一点)，我遇到了一个问题.

I'm in a situation where I need the ASCII value of a character (for Project Euler question #22, if you want to get specific) and I'm running into an issue.

作为 ruby​​ 的新手，我用 google 搜索，发现 ? 是要走的路:?A 或其他.但是当我将它合并到我的代码中时，该语句的结果是字符串 "A"——没有字符代码.[0] 和 slice(0) 的问题相同，理论上两者都应该返回 ASCII 码.

Being new to ruby, I googled it, and found that ? was the way to go: ?A or whatever. But when I incorporate it into my code, the result of that statement is the string "A"—no character code. Same issue with [0] and slice(0), both of which should theoretically return the ASCII code.

我唯一能想到的是这是一个 ruby​​ 版本的问题.我正在使用 1.9.1-p0，今天下午从 1.8.6 升级.我从 Ruby 的工作版本中作弊，在同一个目录中，我想我可能已经有了没有与 .zip 文件捆绑在一起的文件，所以我没有下载它们.

The only thing I can think of is that this is a ruby version issue. I'm using 1.9.1-p0, having upgraded from 1.8.6 this afternoon. I cheated a little going from a working version of Ruby, in the same directory, I figured I probably already had the files that don't come bundled with the .zip file, so I didn't download them.

那么为什么我所有的 ASCII 码都变成了实际的字符呢?

So why exactly are all my ASCII codes being turned into actual characters?

推荐答案

Ruby 1.9 之前的字符处理有些不一致.?a 和 "a"[0] 将返回一个整数，表示字符的 ASCII 值(这通常不是人们正在寻找的行为)，但在实际使用字符通常由一个字符的字符串表示.在 Ruby 1.9 中，字符永远不会神秘地变成整数.如果要获取字符的 ASCII 值，可以使用 ord 方法，如 ?a.ord(返回 97).

Ruby before 1.9 treated characters somewhat inconsistently. ?a and "a"[0] would return an integer representing the character's ASCII value (which was usually not the behavior people were looking for), but in practical use characters would normally be represented by a one-character string. In Ruby 1.9, characters are never mysteriously turned into integers. If you want to get a character's ASCII value, you can use the ord method, like ?a.ord (which returns 97).

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