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It is sometimes necessary to turn off caching on certain pages on a Drupal site. This might be when trying to do something out of the ordinary, like write information to a file, or randomly generate a section of a template. The following code can be used to turn off caching just on the front page of the site.

function theme_preprocess(&$vars, $hook) {
    if ($vars['is_front'] == true) {
        $GLOBALS['conf']['cache'] = false;
    }
}

Adding false to the cache item of the conf globals array at run time will turn off the cache. This is within an if statement that checks to see if the current page is the Drupal front page so it will only be used on the front page.

Opening external links in a new window can be useful, but adding target="_blank" can be a real chore. Not only that, but if you are trying to validate the page to XHTML strict then the target attribute will cause errors to appear as it is not defined in XHTML.

An easy solution to this issue is to add the following JQuery to your site. It will look for any links that start with http and do not contain the current domain and add a new click event to them that causes a new window to be opened. This will exclude most links straight away as they will most likely be relative.

Using file_get_contents() to fetch the contents of a file is quite a common practice. This might be just to get the contents of a text file or to get the ImageCache module in Drupal to pre-cache images. The file_get_contents() function can get a local or remote file and is usually run like this.

$data = file_get_contents($url);

However, when trying to use this function to communicate with an authenticated server you will see the following error appearing.

Although most developers might not like it FTP is quite a common way of deploying the files for a site to the server. To simplify this process Phing comes with a handy FTP transfer action called ftpdeploy.

In order to use the ftpdeploy we first need to install the Net_FTP package. To install this package just enter the following command:

pear install Net_FTP

The first thing we need to create is a build.properties file to store our ftp details

If you have a large page or form that uses validation on it then you will probably want to tell the user that something is going on. One way to do this is by telling the user at the top of the page that something has gone wrong and then letting them figure out where.

A more elegant solution is to scroll the page down the just above the first error message so that the user is aware of what they need to fill in. This can easily be done through a combination of jQuery and the ScrollTo plugin.

The first thing you need on the form is add some tags as the error output elements. Make sure that these tags don't get printed if there are no errors. I have chosen to use p tags with the class of error. Download this plugin and include it within your page.

When creating functions in PHP it is possible to provide default parameters so that when a parameter is not passed to the function it is still available within the function with a pre-defined value. These default values can also be called optional parameters because they don't need to be passed to the function. I have seen this sort of code being used incorrectly quite often recently so I thought I would go over it in a post.

Creating a default parameter in a function is very simple and is quite like normal variable assignment. The following function has a single parameter that is set to 1 if it is not passed when calling the function.

function testFunction($a = 1)
{
    return $a;
}

It is usual when writing a list of items to separate each item with a comma, except the last two items, which are separated with the word "and". I recently needed to implement a function that took a string and converted it into a list of this type so I thought I would expand on it and post it here.

The function takes a single parameter, which can either be an array or a comma separated string. If an array is passed to the function then it is converted into a comma separated string and then passed onto the next part in the function. The function then removes any trailing commas, any commas that have nothing in between them and then makes sure that each comma has a single space after it. The final step is to replace the last comma with the word "and". Once the manipulation is complete then the resulting string is returned. If the string (after removing any trailing commas) doesn't contain any commas then it is simply returned.

I have been playing about with breadcrumb trails in Wordpress recently so I thought I would post the code here in case anyone else finds it useful. The basic idea is to try to find out where the current page is situated within the site. This means checking for pages and categories with their parents. Once we get down to the post level we need to try some things in order to find out where the current post is within the site.

Once the trail array has been filled with items it is looped through and converted into a string.

To use this function put the following code into your functions.php file in your template.

Overloading in PHP describes the way in which properties and methods of an object can be dynamically created or accessed without having to define them first. Traditionally, the word overloading in programming is used to describe accessing object methods with the same name but with different parameters. It is not possible to do this in PHP as it will complain about methods having the same name, so the term describes calling a method or accessing a property that hasn't previously been set or is out of scope. In object orientated terms this means that the method or property is private.

Object Property Overloading

Property overloading allows you to access the property of an object through a method without having to write them first. It can also be used to access any properties that are inaccessible. There are two basic property overloading methods available, these are __set() and __get(), both contain a double underscore (_) in their name.

Using something like CrossSlide is fine if you want fancy effects in your image translations, but for more simple effects you can use a single function to simply swap one image for another. First, lets create some simple markup that will allow us to display some images.