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Remove part of the string before the FIRST dot with js

I have the next problem. I need to remove a part of the string before the first dot in it. I've tried to use split function:
var str = "P001.M003.PO888393";
str = str.split(".").pop();
But the result of str is "PO888393".
I need to remove only the part before the first dot. I want next result: "M003.PO888393".
Someone knows how can I do this? Thanks!

One solution that I can come up with is finding the index of the first period and then extracting the rest of the string from that index+1 using the substring method.
let str = "P001.M003.PO888393";
str = str.substring(str.indexOf('.')+1);
console.log(str)

You can use split and splice function to remove the first entry and use join function to merge the other two strings again as follows:
str = str.split('.').splice(1).join('.');
Result is
M003.PO888393
var str = "P001.M003.PO888393";
str = str.split('.').splice(1).join('.');
console.log(str);

You could use a regular expression with .replace() to match everything from the start of your string up until the first dot ., and replace that with an empty string.
var str = "P001.M003.PO888393";
var res = str.replace(/^[^\.]*\./, '');
console.log(res);
Regex explanation:
^ Match the beginning of the string
[^\.]* match zero or more (*) characters that are not a . character.
\. match a . character
Using these combined matches the first characters in the string include the first ., and replaces it with an empty string ''.

calling replace on the string with regex /^\w+\./g will do it:
let re = /^\w+\./g
let result = "P001.M003.PO888393".replace(re,'')
console.log(result)
where:
\w is word character
+ means one or more times
\. literally .

many way to achieve that:
by using slice function:
let str = "P001.M003.PO888393";
str = str.slice(str.indexOf('.') + 1);
by using substring function
let str = "P001.M003.PO888393";
str = str.substring(str.indexOf('.') + 1);
by using substr function
let str = "P001.M003.PO888393";
str = str.substr(str.indexOf('.') + 1);
and ...

Regex remove all string start with special character

I have a string look like:
var str = https://sharengay.com/movie13.m3u8?pid=144.21.112.0&tcp=none
I want to remove at start ?pid= to end. The result look like:
var str = https://sharengay.com/movie13.m3u8
I tried to:
str = str.replace(/^(?:?pid=)+/g, "");
But it show error like:
Invalid regular expression: /^(?:?pid=)+/: Nothing to repeat

If you really want to do this at the string level with regex, it's simply replacing /\?pid=.*$/ with "":
str = str.replace(/\?pid=.*$/, "");
That matches ?pid= and everything that follows it (.*) through the end of the string ($).
Live Example:
var str = "https://sharengay.com/movie13.m3u8?pid=144.21.112.0&tcp=none";
str = str.replace(/\?pid=.*$/, "");
console.log(str);

You can use split
var str = "https://sharengay.com/movie13.m3u8?pid=144.21.112.0&tcp=none"
var result = str.split("?pid=")[0];
console.log(result);

You can simply use split(), which i think is simple and easy.
var str = "https://sharengay.com/movie13.m3u8?pid=144.21.112.0&tcp=none";
str = str.split("?pid");
console.log(str[0]);

You may create a URL object and concatenate the origin and the pathname:
var str = "https://sharengay.com/movie13.m3u8?pid=144.21.112.0&tcp=none";
var url = new URL(str);
console.log(url.origin + url.pathname);

You have to escape the ? and if you want to remove everything from that point you also need a .+:
str = str.replace(/\?pid=.+$/, "")

You can use split function to get only url without query string.
Here is the example.
var str = 'https://sharengay.com/movie13.m3u8?pid=144.21.112.0&tcp=none';
var data = str.split("?");
alert(data[0]);

how to replace first and last quotes with two different chars in this string "{0}"

I have a string "{0}". I want to replace first quotes with <Q> and second quote with </Q> in javascript.
Can anyone help me with a regex to do this.

I don't have any idea about regex but i thought it seems like this:
var str = "{0}";
var mapObj = {
'{':"<Q>{",
'}':"}</Q>"
};
var re = new RegExp(Object.keys(mapObj).join("|"),"gi");
str = str.replace(re, function(matched){
return mapObj[matched.toLowerCase()];
});
alert(str);
Please correct me, if i'm wrong.

Replace multiple occurences of a comment with javascript

I want to replace multiple occurences of comment and try like below
JsFiddle
Code:
var str = '<!--#test--><!--#test1-->'
str = str.replace('<!--/g', '').replace('-->/g', '');
alert(str)

Your problem is that you're trying to use a string instead of a regular expression. For example, this works.
var str = '<!--#test-->'
str = str.replace(/<!--/g, '').replace(/-->/g, '');
alert(str)

Plain regex commands need to be inside //.
Also, use the
Disjunction; Alternative | (pipe character)
str = str.replace(/<!--|-->/g, ''); // #test#test1

Javascript replace regex wildcard

I have a string which I need to run a replace.
string = replace('/blogs/1/2/all-blogs/','');
The values 1, 2 and all-blogs can change. Is it possible to make them wildcards?
Thanks in advance,
Regards

You can use .* as a placeholder for "zero or more of any character here" or .+ for "one or more of any character here". I'm not 100% sure exactly what you're trying to do, but for instance:
var str = "/blogs/1/2/all-blogs/";
str = str.replace(/\/blogs\/.+\/.+\/.+\//, '');
alert(str); // Alerts "", the string is now blank
But if there's more after or before it:
str = "foo/blogs/1/2/all-blogs/bar";
str = str.replace(/\/blogs\/.+\/.+\/.+\//, '');
alert(str); // Alerts "foobar"
Live example
Note that in both of the above, only the first match will be replaced. If you wanted to replace all matches, add a g like this:
str = str.replace(/\/blogs\/.+\/.+\/.+\//g, '');
// ^-- here
You can read up on JavaScript's regular expressions on MDC.

js> 'www.google.de/blogs/1/2/all-blogs'.replace(/\/blogs\/[^\/]+\/[^\/]+\/[^\/]+\/?/, '');
www.google.de

What about just splitting the string at slashes and just replacing the values?
var myURL = '/blogs/1/2/all-blogs/', fragments, newURL;
fragments = myURL.split('/');
fragments[1] = 3;
fragments[2] = 8;
fragments[3] = 'some-specific-blog';
newURL = fragments.join('/');
That should return:
'/blogs/3/8/some-specific-blog'

Try this
(/.+){4}
escape as appropriate