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Title: variables in PHP part 1 Post by: Daniel Franklin on September 26, 2007, 11:15:03 AM e = "shedboy";
$intDaysInWeek = 7; In the first example the variable identifier in this example is $name and the string value "iain hendry" has been assigned to it . In the second example the variable identifier is $intDaysInWeek and the number 7 is assigned to it . Note that in the number example we do not surround the variable with quotes in this way PHP treats this as a numeric value but if we had put quotes round it then PHP would have treated it as a string. Variable Naming There are some guidelines to follow for naming variables in PHP and these are as follows . 1. All variable names must begin with a letter or underscore character . 2 . The name of the variable can be made up of numbers , letters , underscores but you cant use charcters like + , - , & , £ , * , etc One important thing to note if you are coming from another programming language there is no size limit for variables . Case Sensitivity One thing that causes many hours of hair pulling and anguish is case sensitivity , PHP is case sensitive (some languages are not) . Here is an example of what I mean. <?php $myname = "shedboy"; echo $Myname"; ?> Now we all know what we want to do , declare a variable , assign it the value of "shedboy" and then print this on the screen but in this example we have mis-spelt the variable name , when run the following error is displayed on the screen. Warning: Undefined variable: Myname in D:\testsample.php on line 3 Example Using your favourite HTML editor enter the following <?php $url = "http://www.programmershelp.co.uk"; $rank = 1; echo "Our favourite site is ".$url; echo " "; echo "It is numbered ".$rank; ?> here is the output you should get Our favourite site is http://www.programmershelp.co.uk It is number 1 Articles Source - Free Articles |