当字符串中的单词不由空格分隔时，隐式字符串到脊柱的情况

Question

spinal case is separating words by dashes. i have the following code that works if words are separated by spaces, but not if you have a string where words are NOT separated by spaces like so: "ThisIsSpinalCase", which should return "this-is-spinal-case". can't think of a way to recognize every new word in a str. suggestions?

function spinalCase(str) {
return str.replace(/[\s\W_]/g, "-").toLowerCase();
​
}
​
spinalCase('This_is spinal case'); // returns this-is-spinal-case

edit: i realize i can probably check for when there is a new uppercase letter but this would require adding a space between the last word and the next word

Answer 1

The process is like this:

1. First letter doesn't change anything, so let it out.

2. In the rest of your string, you have two conditions:

   • You just have a space or an underscore, then you should replace it with a dash.
   • You have a capital letter, then you should replace it with a dash followed by that letter.

   However, you can solve these two conditions, with one replace, by using this call of replace replace(/(([AZ])|[\\s_])+/g, "-$2") , this means that:

   • If the regex matches a space or underscore, it'll replace it by just a dash ( $2 will match nothing, because it doesn't match a capital letter).
   • If the regex matches a capital letter, it'll replace it by a dash followed by that letter ( $2 will be have the value of that letter).
3. We concatenate the first letter with the rest (after replacing).
4. We lower-case the result.
5. Done!

Example:

function spinalCase(str) {
  return (str[0] + str.substr(1).replace(/(([A-Z])|[\s_])+/g, "-$2")).toLowerCase();
}