插入转义字符

Question

我想用它们的转义字符值替换和插入转义字符序列，同时考虑到'\'使转义字符无效。

例如

"This is a \n test. Here is a \\n which represents a newline"

在Ruby中实现这一目标的最简单方法是什么？

Answer 1

我认为你正在努力解决以下问题：

"\\n".gsub(/\\\\/, "\\").gsub(/\\n/, "\n") # => "n"
"\\n".gsub(/\\n/, "\n").gsub(/\\\\/, "\\") # => "\\\n"

String#gsub可以使用块参数来执行替换。

str.gsub(/\\(.)/) do |s|
  case $1
  when "n"
    "\n"
  when "t"
    "\t"
  else
    $1
  end
end

这样，首先不会替换任何特殊的转义序列，并且所有转义都可以解决。

Answer 2

你想要与此相反吗？

puts "This is a \n test. Here is a \\n which represents a newline"

=＆GT;

This is a
 test. Here is a \n which represents a newline