使用gsub或delete。区别在于gsub可以删除制表符，而delete不能。有时文件中确实有编辑器添加的选项卡。

a = "\tI have some whitespaces.\t"
a.gsub!(/\s/, '')  #=>  "Ihavesomewhitespaces."
a.gsub!(/ /, '')   #=>  "\tIhavesomewhitespaces.\t"
a.delete!(" ")     #=>  "\tIhavesomewhitespaces.\t"
a.delete!("/\s/")  #=>  "\tIhavesomewhitespaces.\t"
a.delete!('/\s/')  #=>  using single quote is unexpected, and you'll get "\tI have ome whitepace.\t"

现在说这个有点晚了，但是任何在谷歌上搜索这个页面的人都可能对这个版本感兴趣

如果你想清理一大块预先格式化的文本，用户可能以某种方式剪切和粘贴到你的应用程序，但保留单词间距，试试这个:

content = "      a big nasty          chunk of     something

that's been pasted                        from a webpage       or something        and looks 

like      this

"

content.gsub(/\s+/, " ").strip

#=> "a big nasty chunk of something that's been pasted from a webpage or something and looks like this"

gsub方法就可以了。 gsub方法可以在字符串上调用，并说:

a = "this is a string"
a = a.gsub(" ","")
puts a
#Output: thisisastring

gsub方法搜索第一个参数的每一次出现 然后用第二个参数替换它。在这种情况下，它将替换字符串中的每个空格并删除它。

另一个例子:

b = "the white fox has a torn tail"

我们把所有出现的字母t都换成大写的t

b = b.gsub("t","T")
puts b 
#Output: The whiTe fox has a Torn Tail

这里有很多建议，但当我读到你的问题和说“删除所有空白”的具体行时，我想到的是:

" a b c " => "abc"

如果这确实是需要的，你可以做这个简单的操作

wide_string = " a b c "

narrow_string = wide_string.delete(" ")

# you can pass all the different kinds 
# of whitespaces that you want to remove

puts narrow_string # => "abc"

相关回答:

"   clean up my edges    ".strip

返回

"clean up my edges"

Ruby的.strip方法执行与trim()相当的PHP功能。

删除所有空白:

"  leading    trailing   ".squeeze(' ').strip
=> "leading trailing"

@塔斯让我意识到我原来的答案连续删除重复的字母-恶心!从那以后，我改用了压缩方法，如果使用Rails框架，这种方法对这种情况更聪明。

require 'active_support/all'
"  leading    trailing   ".squish
=> "leading trailing"

"  good    men   ".squish
=> "good men"

引用:http://apidock.com/rails/String/squish