Random Web and PHP Notes

Geek Interview Questions:

• What will this do:

  <input type="submit" name="confirm" 
  id="confirm" value="Confirm Request" 
  onclick="return confirm('Really
  Confirm Request?');">

• Explain what JSON is…
• Have you ever created or consumed web services in PHP?
• Explain what REST is…
• What does & do, eg:

  foreach($cust as &$c){
     $c='123';
  }
  
  function foo(&$bar){
     $bar = 'moo';
  }

• How can you use: $x++%2 eg: echo ($x++%2)?’Yes’:’No’;
• What are the function arguments for the mail() command
• What is memcached, have you used it?
• Have you ever done pagination, explain quickly how to paginate a large mysql result.
• What database abstraction classes have you used before.
• Have you used firebug?
• Write this another way:

  <?=($foo)?$bar:$moo;?>

• What does this display?

  preg_match("/^(http://info@)?([^/]+)/i","http://info@abc.com", $data); 
  echo $data[2];

• What will a print_r($_REQUEST); show on these form elements:

  <input type="checkbox" name="box[a]" value=yes> 
  <input type="checkbox" name="box[b]" value=yes>

• What does this print out:

  $v=2; echo $v++%2;

• Do you use <th>’s when writing html?
• Explain what ob_start() does in PHP
• Explain what is wrong with the following JavaScript, if ther is nothing wrong with it, then tell me what it will output:

  var moo = {
          foo: function(){
                  var b = this.a--;
                  alert(--b)
          },
          a: 4
  }
  moo.a=3;
  moo.foo();

• In what way are the JavaScript and Java programming languages related?
• Explain what a fork bomb is
• Is this valid JavaScript:

  var moo = {a : "string", b: 4, c: function(){ alert('moo'); } };

• Do you know what the “short_open_tag” does in php.ini
• What does set_time_limit(0); do in PHP?
• Tell me what the parameter list of the mail() function is.
• Show me how to send a HTML email using the PHP mail() function
• How do you catch an exception in PHP?
• What does json_decode() do in PHP?
• How do you post data to a script via ajax using jQuery?
• Using jQuery, what do you write in the onclick=”” event to hide and show the div?

  <a href="#" onclick="">Hide/Show Div</a>
  <div id="thediv">
        some random content
  </div>

• What does this command do: ssh -g -L 8080:192.168.0.55:80 foo@otherhost -P 2222
• What does this command do: xhost +
• Explain what the suphp apache module does?
• What are the apache2 commands to enable a site called “foo”, it’s valid configuration files is /etc/apache2/sites-available/foo
• Why problems does this cause in Internet Explorer:

  <input type="submit" name="upload" value="Click to upload" 
  onclick="this.disabled=true; this.value='Uploading...';">

• more to come

PHP Stuff:

echo “123”; will print out a capital “S” – the octec value for S is 123.

when posting files from a form, use <form action=”foo.php” method=”post” enctype=”multipart/form-data”> without the enctype the file will not be sent to the server

when storing data in sessions: if there is a session key called $_SESSION[‘products’] and you use $products somewhere in your scripts for a different reason eg: $products=query(“SELECT * FROM…); on some PHP configurations $products and $_SESSION[‘products’] will be the same, so be careful with session key names. you could end up inadvertently messing with session values

if you have an input element <input type=”checkbox” name=”foo[123]” value=”Bar”> PHP will convert foo[123] into an array for you automatically. You can access this like: $foo = $_POST[‘foo’]; echo $foo[“123”]; // this prints Bar

after submitting a form (lets say a sign up form) it is always best to redirect the user to a separate “thank you” page instead of simply displaying a thankyou message at the end of the sign up script. this means if a user refreshes the “thank you” page, it will not sign them up again / throw a nasty re-post warning message in the browser.

<?=($foo)?$bar:$moo;?>

same as:

<? if($foo) echo $bar; else echo $moo; ?>

<input type="checkbox" name="box[a]" value=yes>
<input type="checkbox" name="box[b]" value=yes>
<input type="checkbox" name="box[c]" value=yes>
<input type="checkbox" name="box[d]" value=yes>
print_r($_REQUEST);

json_encode()

while($v<20){
  ?> <tr bgcolor="<?=($v  %2)?'red':'green';?>"><td>fasdf</td></tr> <?
}

preg_match("/^(http://info@)?([^/] )/i","http://info@abc.com", $data);
echo $data[2]; 

HTML:

1. whats a <th> used for
2. how do you create a horizontal css menu using <ul> and <li>

Javascript:

var moo = {
        foo: function(){
                var b = this.a--; 
                alert(--b)
   },
   a: 4
}
moo.a=3;
moo.foo();

// above alerts 2

var moo = {a : "string", b: 4, c: function(){ alert('moo'); } };