Data commit

Task/Pointers-and-references/PHP/pointers-and-references.php

@@ -0,0 +1,28 @@
+<?php
+/* Assignment of scalar variables */
+$a = 1;
+$b =& $a; // $b and $a are now linked together
+$b = 2; //both $b and $a now equal 2
+$c = $b;
+$c = 7; //$c is not a reference; no change to $a or $b
+unset($a); //won't unset $b, just $a.
+
+/* Passing by Reference in and out of functions */
+function &pass_out() {
+    global $filestr;  //$exactly equivalent to: $filestr =& $_GLOBALS['filestr'];
+
+    $filestr = get_file_contents("./bigfile.txt");
+    return $_GLOBALS['filestr'];
+}
+function pass_in(&$in_filestr) {
+    echo "File Content Length: ". strlen($in_filestr);
+
+    /* Changing $in_filestr also changes the global $filestr and $tmp */
+    $in_filestr .= "EDIT";
+    echo "File Content Length is now longer: ". strlen($in_filestr);
+}
+
+$tmp = &pass_out(); // now $tmp and the global variable $filestr are linked
+pass_in($tmp); // changes $tmp and prints the length
+
+?>