booleans in php

Booleans.php

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 <h2 style="color:pink;">use of booleans in php</h2>
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 <?php
  /*
  |------------------------------------------------------------
  | Booleans are the easiest data type was introduced in PHP 4.
  | It can be either TRUE or FALSE and case-insensitive.
  |------------------------------------------------------------
  */
  $bool = true;
  if($bool) echo 'i find a true boolean';
  echo "<br>";
  /*
  |------------------------------------------------------------------
  | control structure automatically converts it's argument to boolean
  | despite that if you want to convert a value to boolean use
  | bool or boolean cast.
  |------------------------------------------------------------------
  */
  $someVar = (bool)100;
  echo $someVar;
  echo "<br>";
  /*
  |------------------------------------------------------------------
  | Following values are considered FALSE while conversion
  | 1. boolean FALSE 
  | 2. integer 0 (zero)
  | 3. float 0.0 (zero)  
  | 4. the empty string, and the string "0" 
  | 5. an array with zero elements
  | 6. an object with zero member variables
  | 7. NULL (including unset variables)
  | 8. SimpleXML objects created from empty tags  
  |------------------------------------------------------------------
  */
  echo "<pre>";
  
  var_dump((bool) true);    // true
  var_dump((bool) false);   // false
  var_dump((bool) 1);    // true
  var_dump((bool) -2);   // true
  var_dump((bool) 0);    // false
  var_dump((bool) 2.3e5);         // true
  var_dump((bool) 0.0);          // false
  var_dump((bool) "");         // false
  var_dump((bool) "modon");      // true
  var_dump((bool) "false");    // true(false is a string and lenght > 0)
  var_dump((bool) array(22));  // true
  var_dump((bool) array());    // false
  
  echo "</pre>";
 ?>
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