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--- docs:tips_n_tricks:php.html [08.03.2012 09:51 CET] – created peter
+++ docs:tips_n_tricks:php.html [08.03.2012 10:23 CET] (current) – peter
@@ Line 2: / Line 2: @@
 ===== Meaning of isset() and empty()  =====
+  ~ $ php --version
+  PHP 5.3.8 (cli) (built: Dec  5 2011 21:24:09)
+  Copyright (c) 1997-2011 The PHP Group
+  Zend Engine v2.3.0, Copyright (c) 1998-2011 Zend Technologies
   <?
+    print "PHP Version is ".phpversion()."\n";
+    print '+---------------';
+    print '+-----------' ;
+    print '+-----------' ;
+    print "+\n";
+    print '| value         ';
+    print '| isset()   ' ;
+    print '| empty()   ' ;
+    print "|\n";
+    print '+---------------';
+    print '+-----------' ;
+    print '+-----------' ;
+    print "+\n";
     print '| $foobar       ';
@@ Line 28: / Line 50: @@
     else               print '| not empty ' ;
     print "|\n";
     print '| $foobar = 42  ';
     $foobar = 42;
@@ Line 60: / Line 82: @@
     else               print '| not empty ' ;
     print "|\n";
+    print '+---------------';
+    print '+-----------' ;
+    print '+-----------' ;
+    print "+\n";
+or
+  <?
+    print "PHP Version is ".phpversion()."\n";
+    print '+-------------------';
+    print '+-----------' ;
+    print '+-----------' ;
+    print "+\n";
+    print '| value             ';
+    print '| isset()   ' ;
+    print '| empty()   ' ;
+    print "|\n";
+    print '+-------------------';
+    print '+-----------' ;
+    print '+-----------' ;
+    print "+\n";
+    printf('| $foobar   %-7s | %-9s | %-9s |'."\n",''       ,(isset($foobar) ? '' : 'not ').'set',(empty($foobar) ? '' : 'not ').'empty' );
+    $foobar = 0;
+    printf('| $foobar = %-7s | %-9s | %-9s |'."\n",'0'      ,(isset($foobar) ? '' : 'not ').'set',(empty($foobar) ? '' : 'not ').'empty' );
+    $foobar = "";
+    printf('| $foobar = %-7s | %-9s | %-9s |'."\n",'""'     ,(isset($foobar) ? '' : 'not ').'set',(empty($foobar) ? '' : 'not ').'empty' );
+    $foobar = 42;
+    printf('| $foobar = %-7s | %-9s | %-9s |'."\n",'42'     ,(isset($foobar) ? '' : 'not ').'set',(empty($foobar) ? '' : 'not ').'empty' );
+      $foobar = "42";
+    printf('| $foobar = %-7s | %-9s | %-9s |'."\n",'"42"'   ,(isset($foobar) ? '' : 'not ').'set',(empty($foobar) ? '' : 'not ').'empty' );
+    $foobar = "x";
+    printf('| $foobar = %-7s | %-9s | %-9s |'."\n",'"x"'    ,(isset($foobar) ? '' : 'not ').'set',(empty($foobar) ? '' : 'not ').'empty' );
+    $foobar = array();
+    printf('| $foobar = %-7s | %-9s | %-9s |'."\n",'array()',(isset($foobar) ? '' : 'not ').'set',(empty($foobar) ? '' : 'not ').'empty' );
+    $foobar = NULL;
+    printf('| $foobar = %-7s | %-9s | %-9s |'."\n",'NULL'   ,(isset($foobar) ? '' : 'not ').'set',(empty($foobar) ? '' : 'not ').'empty' );
+    print '+-------------------';
+    print '+-----------' ;
+    print '+-----------' ;
+    print "+\n";
 gives
+  PHP Version is 5.3.8
+  +---------------+-----------+-----------+
+  | value         | isset()   | empty()   |
+  +---------------+-----------+-----------+
   | $foobar       | not set   | empty     |
   | $foobar = 0   | set       | empty     |
@@ Line 70: / Line 150: @@
   | $foobar = "x" | set       | not empty |
   | $foobar = NULL| not set   | empty     |
+  +---------------+-----------+-----------+