JavaScript question！ I want to write an crush function that can "crush" a string so that it does not contain spaces or dashes and make all letters are lowercase. The function should work like this:...

JavaScript question！

I want to write an crush function that can "crush" a string so that it does not contain spaces or dashes and make all letters are lowercase. The function should work like this:

  input： ABC --> abc (all lowercase)

abc --> abc （correct string dont change)

  A BC --> abc (lowercase, space removed

a -b- c --> abc (lowercase, spaces removed, dash removed)