Javascript – Get extension from filename like variable – Javascript – jQuery

javascriptjquery

I have a varable var file = "testfile.txt"; I am using the following script to find its extension and it works well;

var parts = file.split('.');
var flename = parts[0];
var ext = parts[1];

But if i have a filename with more than one dots, the logic sucks.. It will give txt for filename.txt, but not in the case of file.nam.e.txt or something else.

Anybody suggest me the simplest solution to do this using javascript and(or) jQuery??

Thanks in advance..

Best Answer

Just so you get some alternatives, you can extract it with regular expressions too:

var full = "filename.ext.txt";

// Get all characters before the last dot
var filename = /.*(?=\.)/.exec(full);

// Get the part without dots on the end
var extension = /[^\.]*$/.exec(full);

// If there are no dots in the full name, filename will be empty and extension
// will contain the whole filename. Do some extra processing:
if(!filename){
    filename = full;
    extension = '';
}

Related Solutions

Javascript – Remove properties from objects (JavaScript)

To remove a property from an object (mutating the object), you can do it like this:

delete myObject.regex;
// or,
delete myObject['regex'];
// or,
var prop = "regex";
delete myObject[prop];

Demo

var myObject = {
    "ircEvent": "PRIVMSG",
    "method": "newURI",
    "regex": "^http://.*"
};
delete myObject.regex;

console.log(myObject);

For anyone interested in reading more about it, Stack Overflow user kangax has written an incredibly in-depth blog post about the delete statement on their blog, Understanding delete. It is highly recommended.

If you'd like a new object with all the keys of the original except some, you could use the destructuring.

Demo

let myObject = {
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};

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console.log(myObject); // remains unchanged

Javascript – How to get a timestamp in JavaScript

Short & Snazzy:

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Details:

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(also see this answer or this with further explaination to bitwise operators).

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