December 2013
Intermediate to advanced
384 pages
9h 54m
English
Content preview from jQuery and JavaScript Phrasebook
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Detecting Whether an Array Contains an Item
var food = ["broccoli", "carrots", "spinach"]; var a = food.indexOf("spinach"); // a = 2 var b = food.indexOf("pizza"); // b = -1
The simplest way to check whether an item already exists in an array is to use the .indexOf(item). If the item is found, the index of the first instance is returned; otherwise, –1 is returned.
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.