I have two strings. One is:
"/system/musics/videos/000/000/001/original/%E5%B9%BF%E5%9C%BA%E8%88%9E%E5%BF%AB%E5%9B%9B_-_%E5%A4%A7%E8%8D%89%E5%8E%9F-%E4%BE%AF%E6%AD%8C.MP3"
The second one is:
"广场舞快四_-_大草原-侯歌.MP3"
I want to get:
"/system/musics/videos/000/000/001/original/广场舞快四_-_大草原-侯歌.MP3"
Does anyone know how to find and replace the string in ruby? My idea is to replace the contents after the last '/' with the second string. How can I do it?
first_string = "/system/musics/videos/000/000/001/original/%E5%B9%BF%E5%9C%BA%E8%88%9E%E5%BF%AB%E5%9B%9B_-%E5%A4%A7%E8%8D%89%E5%8E%9F-%E4%BE%AF%E6%AD%8C.MP3"
second_string = "广场舞快四-_大草原-侯歌.MP3"
"#{File.dirname(first_string)}/#{second_string}"
When dealing with filenames, especially if there is a chance your code will be used on multiple operating systems, use the built-in filename manipulation methods dirname and join:
File.join(
File.dirname(
"/system/musics/videos/000/000/001/original/%E5%B9%BF%E5%9C%BA%E8%88%9E%E5%BF%AB%E5%9B%9B_-_%E5%A4%A7%E8%8D%89%E5%8E%9F-%E4%BE%AF%E6%AD%8C.MP3"
),
"广场舞快四_-_大草原-侯歌.MP3"
)
The reason is, File.join and File.dirname are aware of filename delimiters used on a particular OS, courtesy of File::SEPARATOR and File::ALT_SEPARATOR, making them able to split and join the paths correctly.
You'll also often find File.basename and File.extname useful too.
