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Rather than work out how many years have passed since and event, or how old something is, after you get the data from a MySQL database you could use the following query to convert the date on the MySQL side. It works by subtracting the current date from the given date and formatting it in years. Adding the given value to 0 casts the string given by DATE_FORMAT() into an interger.

SELECT DATE_FORMAT(FROM_DAYS(TO_DAYS(now()) - TO_DAYS('2000-07-23 09:20:59')), '%Y') + 0;

This gives the result of 8. You can also pass in just the year, month and day string to the function.

SELECT DATE_FORMAT(FROM_DAYS(TO_DAYS(now()) - TO_DAYS('2000-07-23')), '%Y') + 0;

This gives the result of 38.

The function requires that a properly formatted MySQL date string is found or it will produce an error. The following string used in this function.

FTP connection functions have been built into PHP since version 4 and make transferring files through FTP very easy.

The main function involved is called ftp_connect() which takes a FTP host as a parameter and attempts to connect to it. The port and a timeout limit can also be added to the function if needed.

Once a connection has been made then the ftp_login() function is used to attempt a login. This function returns true on success and false if it fails. The following snippet of code will attempt to connect and login to an FTP server, if any step fails then the code will print out a message saying so.

The MooTools slider is a good little application, and creates a reliable means of adding in a slider tool to a site. However, one thing that the MooTool slider is missing is a block that covers what is on the left hand side of the slider, before the handle.

Create a page with the following HTML.

If for some reason you can't remember your Wordpress password and you can't use the "lost your password" function that comes with Wordpress, due to problems with email, then you can use the following SQL command to reset your password.

UPDATE wp_users SET user_pass = md5('newpassword') WHERE user_login = 'admin';

This can be useful if you have a local web server that you are trying things out on before they go live on the Internet. These servers often don't have access to email as they are just testing platforms and will therefore fail if you try to use the "lost your password" function.

This command has been tested on Wordpress version 2.6.2.

Due to the weakly-typed nature of PHP you can do some odd things, some of which are good, and some of which will enable you to shoot yourself in the foot. Take the following little snippet.

echo '1' + 5;

In some languages this might cause the program to fall over, but PHP will try to evaluate any string into an integer. In this case it converts the string to an integer 1 and adds this to 5 to make 6.

As an aside, if you did this in JavaScript then you would find the opposite result. Because the concatenation character is the same as the addition character JavaScript will always try to truncate the value if any of the present values are a string. So the result in JavaScript would be "15".

If we change the string to a string of "one" and then did the same then the result is 5.

I have previously talked about enable custom field search in Wordpress, but that involved altering the main Wordpress files, which is a big no-no.

So is there an alternative? Well, yes, otherwise I wouldn't have bothered writing the post! To enable custom field (also called Wordpress metadata) searching you need to set up two things.

First you need to have created a custom field (or two) and added this to a number of posts.

Next, you need to have a custom search form that has the name of the field set as the name of an input box. You don't even need the normal s input box that Wordpress uses as default.

Open up your template functions.php file and add in the following three lines of code.

Converting from PostCode to map reference is far from accurate, but it can be done using the Google Maps API. You can get a Google Maps API key from Google by just asking for it, although you are limited to a certain number of requests each day.

Google Maps usually works through JavaScript, but it is possible to ask Google to return the data in JSON format and then use the PHP function json_decode() to decode the information into a usable array format. To get Google to return the data in JSON you must pass the parameter "output=json" in your query string.

The following function can take a postal code and convert it into longitude and latitude.

As the new Google web browser was released last night (I'm writing this post using the new browser) I thought it would be good to update our readers on the user agent string that this web browser has.

The user agent of any browser can be found out by using the userAgent property of the navigator object. This is available in most modern browsers and is thankfully also present in Google Chrome.

navigator.userAgent

As an example the user agent for FireFox 3 on a Windows XP machine looks like this.

Mozilla/5.0 (Windows; U; Windows NT 5.1; en-GB; rv:1.9.0.1) Gecko/2008070208 Firefox/3.0.1

Using the same code, and the same machine, the user agent produced by Google Chrome is as follows.

Use the following code to split a string into an array of characters.

$chars = preg_split('//', $str, -1, PREG_SPLIT_NO_EMPTY);

It uses the preg_split() PHP function which takes a number of parameters. These area as follows:

1. The regular expression to be used. In this case it matches everything.
2. The string to be used in the regular expression.
3. This is the character limit. In this case -1 mean no limit, so the function will work for any size of string.
4. The last parameter can be a flag or series of flags separated by the | character. In this case the PREG_SPLIT_NO_EMPTY flag is used. This prevents the function from returning any empty strings. So if your string has any spaces in it they will not be returned.

To give an example, take the following string variable.

Use the following function to work out how many years have passed since an event. This can be useful if you want to work out a persons age based on their birthday.

The function works by standardising the format of the date using the PHP strtotime() function. This is the first step of the function and sorts out if the date is valid or not. Once this has been done then the date is formatted into a standard form of yyyy-mm-dd, which is then split using the explode() function. The year of the inputted date is then subtracted from the current year, giving the age in years. A final check makes sure that the date hasn't passed yet, and subtracts one from the years value to give a more accurate result. Here is the function: