Filtrare Elementi della tabella

[skinner]

Cercando in internet avrei trovato questo js ma che non riesco a capire bene:

function globaltypes(){
    var globaltype = document.getElementById('alltypes').value;
    var dltypes = document.getElementsByName('type[]');
    for(var i=0; i<dltypes.length; i++){
        dltypes[i].value = globaltype;
    }
}


function adddls(option){
    var dltable = document.getElementById('dltable');
    var idz = document.getElementById('idz').value;
    var downloads = idz.split(",");
    if(option == "clear"){
        while (dltable.firstChild) {
              dltable.removeChild(dltable.firstChild);
        }
        for(var i=0; i<downloads.length; i++){
            var thename = document.getElementById('lol-'+downloads[i]);
            thename.style.color = "Black";
        }
    }else if(option == "all"){ 
        for(var i=0; i<downloads.length; i++){
            if(downloads[i] != ""){
                var dlnamess = document.getElementById('lol-'+downloads[i]).innerHTML; 
                var dllink = document.getElementById('sitepath').value+"?p="+downloads[i];
                var thename = document.getElementById('lol-'+downloads[i]);
                thename.style.color = "Green";
                
                var tr = document.createElement('tr');
                
                var emptytd = document.createElement('td');
                var titletd = document.createElement('td');
    
                var inputtitle = document.createElement('input');
                inputtitle.type = "text";
                inputtitle.name = "title[]";
                inputtitle.value = dlnamess;
                inputtitle.size = 35;
                
                var urltd = document.createElement('td');
                urltd.innerHTML="Url:";
                
                var linktd = document.createElement('td');
                var inputlink = document.createElement('input');
                inputlink.type = "text";
                inputlink.name = "url[]";
                inputlink.value = dllink;
                inputlink.size = 25;
                inputlink.className="input";
                
                var typetd = document.createElement('td');
                var selectt = document.createElement('select');
                selectt.name="type[]";
                selectt.className="select";
                
                //Types
                var app = document.createElement('option');
                app.innerHTML = "1";
                var game = document.createElement('option');
                game.innerHTML = "2";
                var movie = document.createElement('option');
                movie.innerHTML = "3";
                var music = document.createElement('option');
                music.innerHTML = "4";
                var xxx = document.createElement('option');
                xxx.innerHTML = "5";
                var ebook = document.createElement('option');
                ebook.innerHTML = "6";
                var tv = document.createElement('option');
                tv.innerHTML = "7";
                var other = document.createElement('option');
                other.innerHTML = "8";
                            
                
                selectt.appendChild(1);
                selectt.appendChild(2);
                selectt.appendChild(3);
                selectt.appendChild(4);
                selectt.appendChild(5);
                selectt.appendChild(6);
                selectt.appendChild(7);
                selectt.appendChild(8);
                
                typetd.appendChild(selectt);
                titletd.appendChild(inputtitle);
                linktd.appendChild(inputlink);
                
                tr.appendChild(emptytd);
                tr.appendChild(titletd);
                tr.appendChild(urltd);
                tr.appendChild(linktd);
                tr.appendChild(typetd);
                
                dltable.appendChild(tr);
            }
        } 

Il problema è che non riesco a cambiare le variabili da associare alla mia pagina...