• June 8th, 2009
• Posted by TheHahn
• Boise Office, Programming Goodness
• No Comments

Here’s something I wasn’t aware of, if an associated array is populated by a named key, the length is not increased.


var someArray = new Array();
someArray['someKey'] = "someValue";
alert(someArray.length); // expected 1, got blank
alert(someArray['someKey']); // "someValue"


This is a problem if you’re trying to loop the array by jQuery.each(arr, function).


// Same array population
$.each(someArray, function(k,v) {
  alert(k + "|" + v);
});


This will not do anything as jQuery loops by the array length. Given the way our array is set, this WILL work:


// Same array population
for(var k in someArray) {
  alert(k + "|" + someArray[k]);
}


If we change our array to ditch the named key…


var someArray = new Array();
someArray.push("someValue");
$.each(someArray, function(k,v) {
  alert(k + "|" + v);
});


That will work, but that isn’t how I want to do it. This is where I was spacing another method, creating an object instead of an array.


var someArray = new Object();
someArray['someKey'] = "someValue";
$.each(someArray, function(k,v) {
  alert(k + "|" + v);
});


Ah ha! That’s how to rock it.
jQuery.each docs