Using replace combined with regular expressions in JavaScript to achieve the effect of replaceAll_javascript skills

Method:
string.replace(new RegExp(oldString,"gm"),newString))

gm respectively represents:
g=global, m=multiLine
Generally the method is like this Yes, you can replace all specified strings

Another simple method to verify JS:

Enter in the browser address bar
javascript:alert("abcabcabc".replace(new RegExp("a","gm"),"ad"))

This is easier;), I wonder if multiple lines will be convenient