How to replace all characters in a string using JavaScript for this specific case: replace . by _

Question

The following statement in JavaScript works as expected:

var s1 = s2.replace(/ /gi, '_'); //replace all spaces by the character _

However, to replace all occurrences of the character . by the character _, I have:

var s1 = s2.replace(/./gi, '_');

But the result is a string entirely filled with the character _

Why and how to replace . by _ using JavaScript?

Answer 1

The . character in a regex will match everything. You need to escape it, since you want a literal period character:

var s1 = s2.replace(/\./gi, '_');