Wie kann ich Dateierweiterungen mit JavaScript erhalten?

Question

Siehe Code:

var file1 = "50.xsl";
var file2 = "30.doc";
getFileExtension(file1); //returns xsl
getFileExtension(file2); //returns doc

function getFileExtension(filename) {
    /*TODO*/
}

Answer 1

function getExt(filename)
{
    var ext = filename.split('.').pop();
    if(ext == filename) return "";
    return ext;
}

Answer 2

var extension = fileName.substring(fileName.lastIndexOf('.')+1);

Answer 3

Wenn Sie mit Web-Urls arbeiten, können Sie diese verwenden:

function getExt(filepath){
     return filepath.split("?")[0].split("#")[0].split('.').pop();
}

getExt("../js/logic.v2.min.js") // js
getExt("http://example.net/site/page.php?id=16548") // php
getExt("http://example.net/site/page.html#welcome.to.me") // html
getExt("c:\\logs\\yesterday.log"); // log

Demo: https://jsfiddle.net/squadjot/q5ard4fj/

Answer 4

var parts = filename.split('.');
return parts[parts.length-1];

Answer 5

function file_get_ext(filename)
    {
    return typeof filename != "undefined" ? filename.substring(filename.lastIndexOf(".")+1, filename.length).toLowerCase() : false;
    }