в 10:37, 26 мая 2010

2010-05-26T10:37:28Z

Admin: 1 версия

2010-05-26T07:04:58Z

1 версия

Новая страница

==Accessing Function Parameters==



<source lang="html4strict">

<?php
function validatelogin ($username, $password){
$actualuser = "myusername";
$actualpass = "mypassword";

if (strcmp ($username, $actualuser) == 0 && strcmp ($password, $actualpass) == 0){
return true;
} else {
return false;
}
}

if (validatelogin ("myusername","mypassword")){
echo "You are logged in correctly";
} else {
echo "You have an incorrect username and/or password";
}
?>

</source>

==A function that takes a reference for an argument==



<source lang="html4strict">
<?php
$my_int = 10;
print("Before change_value(), \$my_int =" . $my_int . "<br />");

function change_value(&$var) {
$var = 15;
}

change_value($my_int);
print("After change_value(), \$my_int = " . $my_int . "<br />");
?>

</source>

==A Function with an Optional Argument==



<source lang="html4strict">

<html>
<body>
<?php
function headingWrap( $txt, $size=3 ) {
print "<h$size>$txt</h$size>";
}
headingWrap("Book title", 1);
?>
</body>
</html>

</source>

==All optional arguments==



<source lang="html4strict">

<?
function page_header7($color = "336699", $title = "the page", $header = "Welcome") {
print "<html><head><title>Welcome to " . $title . "</title></head>";
print "<body bgcolor="#" . $color . "">";
print "<h1>$header</h1>";
}
// Acceptable ways to call this function:
page_header7(); // uses all defaults
page_header7("66cc99"); // uses default $title and $header
page_header7("66cc99","my wonderful page"); // uses default $header
page_header7("66cc99","my wonderful page","This page is great!"); // no defaults
?>

</source>

==Capturing a return value==



<source lang="html4strict">

<?
function countdown($top) {
while ($top > 0) {
print "$top..";
$top--;
}
print "boom!\n";
}
$counter = 5;
countdown($counter);
print "Now, counter is $counter";
?>

</source>

==Changing argument values==



<source lang="html4strict">

<?
// One optional argument: it must be last
function page_header5($color, $title, $header = "Welcome") {
print "<html><head><title>Welcome to " . $title . "</title></head>";
print "<body bgcolor="#" . $color . "">";
print "<h1>$header</h1>";
}
// Acceptable ways to call this function:
page_header5("66cc99","my wonderful page"); // uses default $header
page_header5("66cc99","my wonderful page","This page is great!"); // no defaults
?>

</source>

==Creating a capitalize function with a default parameter $each==



<source lang="html4strict">

<?php
function capitalize( $str, $each=TRUE ) {
$str = strtolower($str);
if ($each === TRUE) {
$str = ucwords ($str);
} else {
$str = strtoupper($str);
}
echo ("$str <br />");
}
capitalize("hEllo WoRld!");
capitalize("hEllo WoRld!",FALSE);
?>

</source>

==Creating Functions That Take a Variable Number of Arguments==



<source lang="html4strict">

<?php
function addanything (){
$total = 0;
$args = func_get_args ();
for ($i = 0; $i < count ($args); $i++){
if (is_int ($args[$i])){
$total += $args[$i];
}
}
return $total;
}
echo addanything (1,5,7,8,11) . "<br />";
?>

</source>

==Declaring a Function That Requires Arguments==



<source lang="html4strict">
<html>
<head>
<title>Declaring a Function That Requires Arguments</title>
</head>
<body>
<?php
function printBR( $txt ) {
print ("$txt<br>\n");
}
printBR("This is a line");
printBR("This is a new line");
printBR("This is yet another line");
?>
</body>
</html>

</source>

==Declaring a Function with Arguments==



<source lang="html4strict">

<?php
function printcheck ($sometext){
print ("$sometext \n");
}
printcheck ("A.");
printcheck ("AA.");
printcheck ("AAA!");
?>

</source>

==Default Parameters==



<source lang="html4strict">

function doHello($Name = "Paul") {
return "Hello $Name!\n";
}
doHello( );
doHello("Paul");
doHello("Andrew");

</source>

==Define whether a variable is passed by value or reference==



<source lang="html4strict">

<?php
function f1($a) {
$a += 4;
}
function f2(&$a) {
$a += 10;
}
$b = 5;
f1(&$b);
f2($b);
echo "\$b = $b\n";
?>

</source>

==Defining and Calling a two-argument function,==



<source lang="html4strict">

<?
function page_header4($color, $title) {
print "<html><head><title>Welcome to " . $title . "</title></head>";
print "<body bgcolor="#" . $color . "">";
}
?>
//Multiple optional arguments
page_header4("66cc66","my homepage");

</source>

==Function Arguments==



<source lang="html4strict">

<?php
function addup( $a = 32, $b = 32, $c = 32)
{
$total = $a + $b + $c;
echo("$a + $b + $c = $total");
}
?>

<html>
<head>
<title>Function Arguments</title>
</head>
<body>
<h3> <?php addup(8, 16, 24); ?> </h3>
<h3> <?php addup(8, 16); ?> </h3>
</body>
</html>

</source>

==Functions and References==



<source lang="html4strict">

<?php
$val1 = "";
$val2 = "";

function return_multi_value(&$value1, &$value2)
{
$value1 = "This is the first value";
$value2 = "This is the second value";
}

return_multi_value($val1, $val2);
print("$val1<br />$val2<br />");
?>

</source>

==Function with an Optional Argument==



<source lang="html4strict">
<html>
<head>
<title>Function with an Optional Argument</title>
</head>
<body>
<?php
function fontWrap( $txt, $size=3 ){
print "<font size=\"$size\">$txt</font>";
}
fontWrap("call 1<br>",5);
fontWrap("call 2<br>");
fontWrap("call 3<br>");
fontWrap("call 4<br>");
?>
</body>
</html>

</source>

==Function with default parameters==



<source lang="html4strict">
<HTML>
<HEAD>
<TITLE> Printing text on a Web Page</TITLE>
</HEAD>
<BODY>
<?php
function textonweb ($content, $fontsize=3){
echo "<FONT SIZE=$fontsize>$content</FONT>";
}
textonweb ("A <BR>", 7);
textonweb ("AA.<BR>");
textonweb ("AAA. <BR>");
textonweb ("AAAA! <BR>");
?>
</BODY>
</HTML>

</source>

==Function with two parameters==



<source lang="html4strict">

<?
function addNums( $num1, $num2 ) {
$result = $num1 + $num2;
$ret = "<table border=\"1\">";
$ret .= "<tr><td>number 1: </td><td>$num1 </td></tr>";
$ret .= "<tr><td>number 2: </td><td>$num2 </td></tr>";
$ret .= "<tr><td>result: </td><td>$result</td></tr>";
$ret .= "</table>";
return $ret;
}
print addNums (49, 60);
?>

</source>

==Making arguments be passed by reference==



<source lang="html4strict">

<?
function add_some_extra(&$string) {
$string .= "and something extra.";
}
$str = "This is a string, ";
add_some_extra($str);
echo $str;
function foo ($bar) {
$bar .= " and something extra.";
}
$str = "This is a string, ";
foo ($str);
echo $str;
foo (&$str);
echo $str;
?>

</source>

==Passing an Argument to a Function by Value==



<source lang="html4strict">

<html>
<head>
<title>Passing an Argument to a Function by Value</title>
</head>
<body>
<?php
function addFive( $num ) {
$num += 5;
}
$orignum = 20;
addFive( $orignum );
print( $orignum );
?>
</body>
</html>

</source>

==Passing By Reference==



<source lang="html4strict">

function square1($number) {
return $number * $number;
}
$val = square1($val);
function square2(&$number) {
$number = $number * $number;
}
square2($val);

</source>

==Passing Variables as a Reference to the Argument of a Function==



<source lang="html4strict">
<?php
function somefunct ($somearg){
$somearg += 3;
}
$othernum = 12;
somefunct ($othernum);
echo "$othernum","\n";

somefunct (&$othernum);
echo "$othernum","\n";
?>

</source>

==Using a Function Call to Pass an Argument to a Function by Reference==



<source lang="html4strict">

<html>
<head>
<title>Using a Function Call to Pass an Argument to a Function by Reference</title>
</head>
<body>
<?php
function addFive( $num ){
$num += 5;
}
$orignum = 20;
addFive( &$orignum );
print( $orignum );
?>
</body>
</html>

</source>

==Using Optional Parameters==



<source lang="html4strict">

<?php
$access = array("a", "c", "h", "r", "r");
$admin = array("e", "q");
function check_access($username, $adminonly = false) {
global $access, $admin;
if (in_array($username, $admin)) {
return true;
}
if (!($adminonly) && in_array($username, $access)) {
return true;
}
return false;
}
echo check_access("r") ? "is" : "is NOT" ," allowed.</p>";
echo check_access("q") ? "is" : "is NOT" ," allowed.</p>";
echo check_access("r", true) ? "is" : "is NOT" ," an admin.</p>";
echo check_access("q", true) ? "is" : "is NOT" ," an admin.</p>";
?>

</source>

← Предыдущая	Версия 10:37, 26 мая 2010
(нет различий)

PHP/Functions/Parameters - История изменений

в 10:37, 26 мая 2010

Admin: 1 версия