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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:

If you want to display a Wordpress front page in a new or interesting way by splitting the categories into sections, or by not displaying certain categories at all then you can use the query_posts() function. This function comes as part of Wordpress and allows you to override the queries that are being executed behind the scenes. This basically controls what posts are seen by "the loop". In order for the function to work it must be called before "the loop", look out for this line (or similar):

<?php if ( have_posts() ) : while ( have_posts() ) : the_post(); ?>

And put the call to query_posts() before that. You will need to give it certain parameters in order to do something.

So what can you do with this function? Well all sorts of stuff, but for this post we are just interested in getting different categories out, so lets concentrate on that.

If you are running FireFox (or Chrome) then there is a handy little short cut you can use to view the source of a page you are looking at. If you add the text view-source on any web address then you will see the equivalent of viewing the source of a page (perhaps by pressing Ctrl+u). Although not entirely useful, it does have a couple of benefits, such as being able to view your code in another tab, rather than another window.

Unfortunately, this only works in FireFox up to the latest version (currently 3). I have tested this in IE 7, Opera and Safari and they all complain about invalid protocols. Apparently it used to work in IE 6 before SP2, but was removed with that patch. This leads me to believe that it is not really a protocol, but a command that the browser understands on a local level. Much in the same way as about:config works.

If you want to give your users a little snippet of code it is nice to give them the option of selecting the entire block of code without having to highlight the text manually. This can be done with a simple JavaScript button.

Take the following form:

<form name="aForm">
<textarea name="aTextarea" cols="50" rows="20">
Copy this text onto your own website.
</textarea>
</form>

To enable the selection functionality you just need to add in an input button. The click event of this button will be to run a JavaScript bookmarklet that focuses on the textarea in question (in this case it is called aTextarea) and selects the text.

I really don't know how this would be useful, but it might teach you a couple of things about how to use the browser window functions and properties.

The following function resizes the browser window to nothing and then gradually increases this to full screen in a series of steps, at each step the window is moved so that it is in the middle of the screen. This in effect makes it look like the browser window is zooming in.

function warpSpeedWindow(){
 for(i = 0;i < 50;i++){
  window.moveTo(screen.availWidth * -(i - 50) / 100, screen.availHeight * -(i - 50) / 100);
  window.resizeTo(screen.availWidth * i / 50, screen.availHeight * i / 50);
 }
 window.moveTo(0,0);
 window.resizeTo(screen.availWidth, screen.availHeight);
}

You can call this function on the page load by using the following:

XDebug is an excellent debugging solution that will give you a more detailed indication of what is wrong in your code. Here is an example of trying to divide two variables that have a value of 0.

The PHP function preg_replace() has powerful functionality in its own right, but extra depth can be added with the inclusion of the e modifier. Take the following bit of code, which just picks out the letters of a string and replaces them with the letter X.

$something = 'df1gdf2gdf3sgdfg';
$something = preg_replace("/([a-z]*)/", "X", $something);
echo $something; // prints XX1XX2XX3XX

This is simple enough, but using the e modifier allows us to use PHP functions within the replace parameters. The following bit of code turns all letters upper case in a string of random letters by using the strtoupper() PHP function.