In this next article, we will discuss and demonstrate how to pass values in the correct order to a function. When a function is expected to perform a certain task and the values are not passed in a certain order, the function will not produce the correct result. The function always receives the values in the order they are passed as shown below:
function functionx ($x, $y, $z);
Call the function as follows:
functionx ($var1, $var2, $var3, $var4);
function sets $w=$var1, $x=$var2, $y=$var3, and z=$var4).
The function definition to compute the sales tax should resemble code shown below:
function compute_salestax($amount, $clientState, $salestaxrate);
$amount is the cost of the order, and $clientState is the state the client is located in. If you were to call the function as follows:
compute_salestax($clientState, $amount, $salestaxrate);
The function would use the value of the $clientState variable as the cost of the order, and the value of the $amount would be set as the $clientState variable. The function would not compute correctly.
I have installed and used a newer version of the Wampserver package for this program. The newer version is Wampserver (64 bits & PHP 5.5) 2.5, which includes the newer releases of .. Apache : 2.4.9 MySQL : 5.6.17 PHP : 5.5.12 PHPMyAdmin : 4.1.14 SqlBuddy : 1.3.3 XDebug : 2.2.5
Please refer to the following articles for the download, install, configuration and fixing the security hole.
NOTE: As demonstrated in the previous programs, we used notepad a plain text editor. The PHP programs are stored on our web server, "C:\Wampserver\www." Please note the stored web server location.
Now let us create the PHP program, please follow the steps outlined below:
- Select and click "Start."
- Select and click "All Programs."
- Select and click "Accessories."
- Select and click "Notepad."
- Type the PHP code exactly as shown below.
<title>Calculate Sales Tax</title>
<body><h1>Calculate Sales Tax</h1>
<h3>Demonstrates passing values in the correct order to functions<h3>
$amount = 2000.00;
$salestaxrate = .07;
$clientState = "Virginia";
compute_salestax($amount, $clientState, $salestaxrate);
function compute_salestax($amount, $clientState, $salestaxrate)
$salestax = $amount * $salestaxrate;
print "$$salestax sales tax for the State of $clientState.<p />";
- Once you have type the entire program, Select "File," "Save As," and then go to the webroot of your server. For example, C:\Wampserver\www. Type Filename, salestaxcom.php," and then Select "Save."
In the next article of the Using functions in a PHP program (part 8); we will continue with Passing the right number of values to a function in a PHP Program.