How to use jQuery .each to operate differently on a subset of matched objects

Question

Hi,

I'm using latest jQuery (via the Google CDN) and am using this code to build a TOC:

$("#infoArticles h2, #infoArticles h3").each(function(i) {
    var current = $(this);
    current.attr("id", "title" + i);
    $("#toc").append("<li><a id='link" + i + "' href='#title" + i + "' title='" + current.attr("tagName") + "'>" + current.html() + "</a></li>");
});

Works a treat.

I want the .each loop to treat matched h2's differently from matched h3's in order that I may add a class to the li's resulting from h2's.

Any helpful comments, most appreciated and gratefully received!

Answer 1

Check the nodeName or tagName.

$("h2").each(function(i){
  alert(this.nodeName + " " + i); // Alerts 'H2 0,' 'H2 1,' etc.
});

Answer 2

$("#infoArticles h2, #infoArticles h3").each(function(i) {
    var current = $(this);
    current.attr("id", "title" + i);
    if(this.tagName == "H2"){
      //h2
    }else{
      //h3
    }
    $("#toc").append("<li><a id='link" + i + "' href='#title" + i + "' title='" + current.attr("tagName") + "'>" + current.html() + "</a></li>");
});

Answer 3

You create a function out of your code and call it with different parameters:

$("#infoArticles h2").each(function(i) {
    myFunction("ma-classe");
});
$("#infoArticles h3").each(function(i) {
    myFunction();
});

function myFunction(class=""){
   var current = $(this);
    current.attr("id", "title" + i);
    $("#toc").append("<li class='"+class+"'><a id='link" + i + "' href='#title" + i + "' title='" + current.attr("tagName") + "'>" + current.html() + "</a></li>");
}

Answer 4

Note that Append is expensive, so, for the sake of optimisation, you should move the append() function out of your loop, to only do it once instead of for each selected element.

var htmlToInsert = null;
$("#infoArticles h2, #infoArticles h3").each(function(i) {
    var current = $(this);
    current.attr("id", "title" + i);
    if(this.tagName == "H2"){
      //h2
    }else{
      //h3
    }
    htmlToInsert += "<li><a id='link" + i + "' href='#title" + i + "' title='" + current.attr("tagName") + "'>" + current.html() + "</a></li>";

});
$("#toc").append(htmlToInsert);