Structure of a Serialized PHP string

Question 1

I was wondering if anyone could point me to a resource where the details of a serialized php string is documented. I would basically like to know the format/structure so I can write a function in VB.NET to serialize/deserialize it back.

Thanks!

Question 2

The basic structure is as follows:

Scalar types:

Booleans are serialized as:
```
b:;
```
where  is an integer with a value of either 0 (false) or 1 (true).
Integers are serialized as:
```
i:;
```
where  is the integer value.
Floats are serialized as (with d meaning double):
```
d:<f>;
```
where <f> is the float value.
Strings are serialized as:
```
s::"<s>";
```
where  is an integer representing the string length of <s>, and <s> is the string value.

Special types:

null is simply serialized as:
```
N;
```

Compound types:

Arrays are serialized as:
```
a::{<elements>}
```
where  is an integer representing the number of elements in the array, and <elements> zero or more serialized key value pairs:
```
<key><value>
```
where <key> represents a serialized scalar type, and <value> any value that is serializable.
Objects are serialized as:
```
O::"<s>"::{<properties>}
```
where the first  is an integer representing the string length of <s>, and <s> is the fully qualified class name (class name prepended with full namespace). The second  is an integer representing the number of object properties. <properties> are zero or more serialized name value pairs:
```
<name><value>
```
where <name> is a serialized string representing the property name, and <value> any value that is serializable.

There's a catch with <name> though:

<name> is represented as
```
s::"<s>";
```
where  is an integer representing the string length of <s>. But the values of <s> differs per visibility of properties:

a. With public properties <s> is the simple name of the property.

b. With protected properties, however, <s> is the simple name of the property, prepended with * — an asterix, enclosed in two NUL characters (i.e. chr(0)).

c. And with private properties, <s> is the simple name of the property, prepended with <s> — <s>, enclosed in two NUL characters, where <s> is the fully qualified class name.

There are a few other cases, such as R:;, that represents references, that I haven't mentioned here (because I honestly haven't figured out the exact workings of it yet), but this should give you a decent idea about PHP's serializing mechanism.

Question 3

There's no real reason to use regexes here, you can use string and array functions instead.

You can explode the part after the ? (which you can get using substr to get a substring and strrpos to get the position of the last ?) into an array, and use unset to remove arg3, and then join to put the string back together.:

$string = "http://domain.com/php/doc.php?arg1=0&arg2=1&arg3=0";
$pos = strrpos($string, "?"); // get the position of the last ? in the string
$query_string_parts = array();

foreach (explode("&", substr($string, $pos + 1)) as $q)
{
  list($key, $val) = explode("=", $q);
  if ($key != "arg3")
  {
    // keep track of the parts that don't have arg3 as the key
    $query_string_parts[] = "$key=$val";
  }
}

// rebuild the string
$result = substr($string, 0, $pos + 1) . join($query_string_parts);

See it in action at http://www.ideone.com/PrO0a

Question 4

You need a Ajax call to pass the JS value into php variable

JS Code will be (your js file)

var jsString="hello";
$.ajax({
    url: "ajax.php",
    type: "post",
    data: jsString
});

And in ajax.php (your php file) code will be

$phpString = $_POST['data'];     // assign hello to phpString

Question 5

$edited = stristr($sentence, $word);
$edited = str_ireplace($word, '<span class="found">'.$word.'</span>', $edited);

Demo.

Or better yet (preserves the original case and only bolds whole $words):

$edited = stristr($sentence, $word);
$edited = preg_replace('~b(' . preg_quote($word, '~') . ')b~i', '<span class="found">$1</span>', $edited);

Another demo.

Question 6

You could use the JSON format that is already implemented in several languages.

Structure of a Serialized PHP string

Answers

php,string,serialization