Today, in 2021 you can use the replaceAll function:

let str = "Hello. My name is John."

let newStr = str.replaceAll('.', '')

console.log(newStr) // result -> Hello My name is John

let nextStr = str.replaceAll('.', '&')

console.log(nextStr) // result -> Hello& My name is John&

RegEx instance properties used g , i

global : Whether to test the regular expression against all possible matches in a string, or only against the first.

ignoreCase : Whether to ignore case while attempting a match in a string.

RegEx special characters used [a-z] , +

[^xyz] : A negated or complemented character set. That is, it matches anything that is not enclosed in the brackets. You can specify a range of characters by using a hyphen.

For example, [abcd] is the same as [a-d]. They match the 'b' in "brisket" and the 'c' in "chop".

+ : Matches the preceding item 1 or more times. Equivalent to {1,}.

JavaScript string replace method syntax

str.replace(regexp|substr, newSubStr|function[, Non-standard flags]);

The non-standard flags g & i can be passed in the replace syntax or built into the regex. examples:

var re = /[^a-z]+/gi;   var str = "this is a string";   var newstr = str.replace(re, "");   print(newstr);

var str = "this is a string";   var newstr = str.replace(/[^a-z]+/, "", "gi");   print(newstr);

To match whitespace characters as well \s would be added to the regex [^a-z\s]+.

JavaScript Reference

$('.hourfield').focusout(function() {

    var h;
    var m;
    var timeStr = "";
    var CleanTimeStr = "";
    var newFormat = "";

    timeStr = $(this).val();

I did some minor changes to the replace() rule and just removed the "dots" which was the main purpose

    CleanTimeStr = timeStr.replace(/[.]+/g,"");

    if(CleanTimeStr > 0) {

        h = CleanTimeStr.substr(0,2);
        m = CleanTimeStr.substr(2,2);

        newFormat = h+':'+m;

        //Add new values
        $(this).val(newFormat);
    }
});

So now it works fine, thanks!