How to trim a file extension from a String in JavaScript?

Question

For example, assuming that x = filename.jpg, I want to get filename, where filename could be any file name (Let\'s assume the file nam

Answer 1

This is where regular expressions come in handy! Javascript's .replace() method will take a regular expression, and you can utilize that to accomplish what you want:

// assuming var x = filename.jpg or some extension
x = x.replace(/(.*)\.[^.]+$/, "$1");

Answer 2

Another one liner - we presume our file is a jpg picture >> ex: var yourStr = 'test.jpg';

    yourStr = yourStr.slice(0, -4); // 'test'

Answer 3

You can use path to maneuver.

var MYPATH = '/User/HELLO/WORLD/FILENAME.js';
var MYEXT = '.js';
var fileName = path.basename(MYPATH, MYEXT);
var filePath = path.dirname(MYPATH) + '/' + fileName;

Output

> filePath
'/User/HELLO/WORLD/FILENAME'
> fileName
'FILENAME'
> MYPATH
'/User/HELLO/WORLD/FILENAME.js'

Answer 4

If you have to process a variable that contains the complete path (ex.: thePath = "http://stackoverflow.com/directory/subdirectory/filename.jpg") and you want to return just "filename" you can use:

theName = thePath.split("/").slice(-1).join().split(".").shift();

the result will be theName == "filename";

To try it write the following command into the console window of your chrome debugger: window.location.pathname.split("/").slice(-1).join().split(".").shift()

If you have to process just the file name and its extension (ex.: theNameWithExt = "filename.jpg"):

theName = theNameWithExt.split(".").shift();

the result will be theName == "filename", the same as above;

Notes:

1. The first one is a little bit slower cause performes more operations; but works in both cases, in other words it can extract the file name without extension from a given string that contains a path or a file name with ex. While the second works only if the given variable contains a filename with ext like filename.ext but is a little bit quicker.
2. Both solutions work for both local and server files;

But I can't say nothing about neither performances comparison with other answers nor for browser or OS compatibility.

working snippet 1: the complete path

var thePath = "http://stackoverflow.com/directory/subdirectory/filename.jpg";
theName = thePath.split("/").slice(-1).join().split(".").shift();
alert(theName);

working snippet 2: the file name with extension

var theNameWithExt = "filename.jpg";
theName = theNameWithExt.split("/").slice(-1).join().split(".").shift();
alert(theName);

working snippet 2: the file name with double extension

var theNameWithExt = "filename.tar.gz";
theName = theNameWithExt.split("/").slice(-1).join().split(".").shift();
alert(theName);

Answer 5

This is the code I use to remove the extension from a filename, without using either regex or indexOf (indexOf is not supported in IE8). It assumes that the extension is any text after the last '.' character.

It works for:

• files without an extension: "myletter"
• files with '.' in the name: "my.letter.txt"
• unknown length of file extension: "my.letter.html"

Here's the code:

var filename = "my.letter.txt" // some filename

var substrings = filename.split('.'); // split the string at '.'
if (substrings.length == 1)
{
  return filename; // there was no file extension, file was something like 'myfile'
}
else
{
  var ext = substrings.pop(); // remove the last element
  var name = substrings.join(""); // rejoin the remaining elements without separator
  name = ([name, ext]).join("."); // readd the extension
  return name;
}

Answer 6

I don't know if it's a valid option but I use this:

name = filename.split(".");
// trimming with pop()
name.pop();
// getting the name with join()
name.join('.'); // we split by '.' and we join by '.' to restore other eventual points.

It's not just one operation I know, but at least it should always work!

UPDATE: If you want a oneliner, here you are:

(name.split('.').slice(0, -1)).join('.')