Friday, February 1, 2013

Using jQuery to include a supporting file

There are times when you'll want to include a file from your server in a page, but don't have access to server-side code like ASP's include directive.  For instance, you may be working in pure HTML, and want to include a navigation menu on every page without duplicating it each time.  You may be tempted to use an iframe for that, or render it with a javascript function full of document.write statements.  Both are options, and have their uses, but jQuery offers another solution: the .load() method.  It is very similar to the .get() function, except that it assumes a few defaults, and has an extra option for only inserting a certain part of the returned content.

Friday, January 25, 2013

Internet Explorer's Developer Tools (F12) Overview

Developing a web page is not always a simple matter of creating code on your computer, uploading it to the server and it works.  The interaction of your page, CSS stylesheets, javascript code (sometimes yours, sometimes external) and the framework of other files that may wrap around your code often produce odd results that you need to debug within the browser itself to figure out.  Until browser-based developer tools like Microsoft's F12 Developer Tools or Firebug came along, all you could do was view the source of your page and stare until you went cross-eyed.  Now that these tools exist, by all means use them!  I plan to write a series of posts about developer tools, starting with this overview of Microsoft's F12 Developer Tool.

Friday, January 18, 2013

Mixed security pages: How to avoid error messages

Depending on what browser and what version you use, the dialog box will appear differently.  The message is still the same though: You're viewing a secure page (https://...) and a warning pops up that there is some insecure content mixed in, asking you what to do about it.  It happens on small sites, corporate sites, even banks, social networking and other very large sites that should have the technical know-how not to scare you like that.  (This can be especially scary when you get security messages from your bank's website!)

Thursday, January 17, 2013

Submitting Forms: Don't Forget the NAME Attribute...

Just a quick post on something I stumbled across recently... I was submitting a form with several checkboxes and text fields, but no matter what I did on the receiving page, it wasn't getting any values from either POST or GET data. At first I assumed I was doing something wrong in PHP, since I'm new to the language and have been doing forms for many years. It wasn't until I was thoroughly frustrated and finally searched Google for help that I slapped my forehead and had it solved within seconds.  Hopefully, I can give you the same head-slapping moment with less frustration.

Monday, November 12, 2012

Hiding elements from printing

The question comes up all the time: Can I prevent people from printing my web page or an image on the page?  The short answer is unfortunately "No".  You can make it difficult for them, but a determined visitor will still find ways.  So far nothing I'm aware of can prevent them altogether.  Basically, if you put it on the page, they can see it and find a way to print it.

Another way of looking at the same problem is removing elements of your page that don't need to be printed.  For instance, if somebody is reading an article on your site and wants to print it, they probably don't need the navigation, advertisements or a print button on the printed page.  They want to read the article, not look at the framework around it.

Wednesday, November 7, 2012

Doctypes: What are they and why should you care?

Imagine walking into a room where everyone speaks english, but they all come from different countries, and different sections of each country.  It's all the same language, but the words they use can mean different things to each person.  For instance, somebody from England might ask you to "fetch a torch from the boot".  To an American, that wouldn't make much sense unless you knew to expect the British version of English.  Then you'd know that he was asking you to get a flashlight from the trunk of his car.

A doctype can be thought of as a definition of what variation of language your page is written in.  If you don't specify a doctype, each browser will try to interpret things their own way and the results can either be subtly different or completely off, so a doctype should be considered mandatory.  Unfortunately, they are very often forgotten about until after you've spent hours or even days trying to figure out why your page isn't working as it should.

Thursday, November 1, 2012

jsFiddle - A site for debugging

Sometimes you just need an environment where you can put together your HTML, CSS and javascript without having to build a server, install different javascript libraries, build your page and all that... you just want to see how this fragment of code would work.  Or you need to show another developer how a certain bit of jQuery or CSS works and you don't have a site they can access.  Maybe you can't get it working, and want to ask your favorite support forum for help?  There are many sites out there which can help, including one that I use for many of my posts here on jUntangled as well as when I'm helping other members of Experts-Exchange with questions they have.  I heard good things about jsFiddle for this purpose, and signed up for a free account there.  Here's what I found...