PHP If-Abfragen, Schleifen, Funktionen

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Revision as of 10:54, 10 January 2023 by 85.31.21.47 (talk) (→‎Beispiel 1)
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Entscheidungen durch if-Abfragen[edit]

Beispiel 1[edit]
<?php
$var1 = 2;
$var2 = 7;
if($var1 < 5 || $var2 == 7) {
  print "Variable 1 ist kleiner als 5 oder Variable 2 beträgt 7";
}
?>
Beispiel 2[edit]
<?php
$var1 = 2;
$var2 = 7;
if(!($var2 < 5)) {
  print "Variable 2 ist nicht kleiner als 5";
}
?>


Else und elseif[edit]

Beispiel 1[edit]
<?php
if($gender == "m") {
  print "<h1>Hallo Herr ".$lastname."!</h1>\n";
} elseif ($gender == "w") {
  print "<h1>Hallo Frau ".$lastname."!</h1>\n";
} else {
  print "Hi du";
}
?>
Beispiel 2[edit]
<?php
if($gender == "m") {
  print "<h1>Hallo Herr ".$lastname."!</h1>\n";
} else {
  print "<h1>Hallo Frau ".$lastname."!</h1>\n";
}
?>


While und For-Schleife[edit]

Beispiel 1[edit]
<?php
for ($i= 0; $i < 10; $i++) {
  print "<p>Zehnmal Hallo</p>\n";
}
?>
Beispiel 2[edit]
<?php
$i = 0;
while ($i < 10) {
  $i++;
  print $i*$i."<br>\n";
}
?>
Beispiel 3[edit]
<?php
$product[0]['ProductName'] = "Semmel";
$product[0]['Price'] = 1.99;
$product[0]['Amount'] = 6;
$product[1]['ProductName'] = "Kornspitz";
$product[1]['Price'] = 1.49;
$product[1]['Amount'] = 0;
$product[2]['ProductName'] = "Laugenbrezl";
$product[2]['Price'] = 2.99;
$product[2]['Amount'] = 8;
$i = 0;

/*count returned die Länge des Arrays (ähnlich wie .length)*/

while ($i < count($product)) {
  if($product[$i]['Amount'] > 0) {
    print "<p>Product: " .$product[$i]['ProductName']. " Price: "
      .$product[$i]['Price']. " Euro</p>\n";
  }
  $i++;
}
?>

Foreach Schleifen[edit]

Beispiel 1[edit]
<?php
$product = array(
  1, "Bohrmaschine", 45, "Kraftvolle Bohrmaschine für Handwerker", 23
);
foreach ($product as $item) { 
  print $item . "<br>\n";
}
?>
Beispiel 2[edit]
<?php
$product[0]['ProductName'] = "Bohrmaschine";
$product[0]['Price'] = 45.99;
$product[0]['Amount'] = 6;
$product[1]['ProductName'] = "Kreissäge";
$product[1]['Price'] = 79.99;
$product[1]['Amount'] = 0;
$product[2]['ProductName'] = "Bandschleifer";
$product[2]['Price'] = 85.99;
$product[2]['Amount'] = 11;

foreach($product as $content) {
  if($content['Amount'] > 0) {
    print "<p>Produkt: " .$content['ProductName'].
      " Preis: " .$content['Price']. " Euro.</p>\n";
  }
}
?>
Beispiel 3[edit]
<?php
$product[0]['ProductName'] = "Bohrmaschine";
$product[0]['Price'] = 45.99;
$product[0]['Amount'] = 6;
$product[1]['ProductName'] = "Kreissäge";
$product[1]['Price'] = 79.99;
$product[1]['Amount'] = 0;
$product[2]['ProductName'] = "Bandschleifer";
$product[2]['Price'] = 85.99;
$product[2]['Amount'] = 11;
foreach($product as $level1) {
  foreach($level1 as $level2) {
    print $level2. "<br>\n";
  }
  print "<br>";
}
?>
Beispiel 4[edit]
<?php
$product[0]['ProductName'] = "Bohrmaschine";
$product[0]['Price'] = 45.99;
$product[0]['Amount'] = 6;
$product[1]['ProductName'] = "Kreissäge";
$product[1]['Price'] = 79.99;
$product[1]['Amount'] = 0;
$product[2]['ProductName'] = "Bandschleifer";
$product[2]['Price'] = 85.99;
$product[2]['Amount'] = 11;
foreach($product as $level1) {
  foreach($level1 as $name => $level2) {
    print $name . ": " .$level2. "<br>\n";
  }
  print "<br>";
}
?>

Funktionen in PHP[edit]

// BPS 1
function greeting() {
  print "Guten Morgen";
}
greeting();

// BPS 2
function greeting($text) {
  print $text;
}
greeting("Guten Morgen");

// BSP 3
function greeting($text, $salutation) {
  print $text . " " . $salutation;
}
$greet = "Guten Morgen";
$reader = "Herr Müller";
greeting($greet, $reader);


Rückgabewerte der Funktionen[edit]

Beispiel 1[edit]
<?php 
function doubleValue($value) {
  $value = $value*2;
  return $value;
}
print doubleValue(5);
/* oder */
function doubleValueAlternative($value) {
  return ($value*2);
}
print doubleValueAlternative(5);
?>
Beispiel 2[edit]
<?php 
function doubleAndPowerOf2($value) {
  $double = $value*2;
  $powerOf2 = $value*$value;
  $result = array(
    'Verdopplung' => $double,
    'Quadrat' => $powerOf2
  );
  return $result;
}
$returnValue = doubleAndPowerOf2(3);
$doubleValue = $returnValue['Verdopplung'];
$valuePowerOf2 = $returnValue['Quadrat'];
print "Der doppelte Wert dieser Zahl beträgt " . $doubleValue .".<br>\n";
print "Das Quadrat dieser Zahl beträgt " . $valuePowerOf2 .".<br>\n";
?>

Eine Funktion in das PHP-Programm einbinden[edit]

File: doubleValue.php

<?php 
    function doubleValue($value){
    return ($value * 2);
}
?>
File: MainFile

<?php
    include("doubleValue.php");
    print doubleValue(4);
?>