JavaScript: Finding a value in an Object Array

Question

I've got an array of objects defined like this:

var editionsObj = new Array();
function editionObject(name,description)
{
 this.name = name;
 this.description = description;
}

I need to search the editionsObj array for the existence of a variable in the name field. If no object in array has a name value equal to what I need, I'm going to insert it into the array. I've seen some examples in jQuery but wasn't able to get any to work.

Thanks in advance!

Answer 1

Was able to solve this with code similar to the following:

var objCheck = null;
objCheck = jQuery.grep(editionsObj, function(n, i) {
 return n.name == currentEdition;
});
if ((objCheck == null) || (objCheck.length == 0))
{
 editionsCount++;
 editionsObj[editionsCount] = new editionObject(currentEdition,currentFamily,'');
}

Basically it performs a grep on the object array checking a certain index (name) for the value. If the value doesn't exist, then I perform the add.

Hope it helps someone else!

Answer 2

I'm going to assume that each element of your array has only two properties. If that's correct, then forget the idea of having named properties and just use a JS object:

var editionsObj = {};
function addIfNotExists(name,description){
 if(!(name in editionsObj)) editionsObj[name] = description;
}

• lsuarez: From the context of the variable name convention, it looks like it's possible items with the same "names" will have several "editions." Might need more info to determine if this is a viable solution.
• ic3b3rg: I took If no object in array has a name value equal to what I need, I'm going to insert it into the array to mean that there's only description per name, but I suppose it could be interpreted differently.

Answer 3

A simple for loop should suffice:

var nameToSearchFor = 'Bob',
 desc = 'whatever',
 alreadyExists = false;
for (var i = 0, il = editionsObj.length; i < il; i++) {
 if (editionsObj[i].name === nameToSearchFor) {
 alreadyExists = true;
 break;
 }
}
if (!alreadyExists) {
 editionsObj.push(new editionObject(nameToSearchFor, desc));
}