(PHP 4, PHP 5, PHP 7)
print_r — Prints human-readable information about a variable
print_r ( mixed $expression [, bool $return = false ] ) : mixed
print_r() displays information about a variable in a way that's readable by humans.
print_r(), var_dump() and var_export() will also show protected and private properties of objects. Static class members will not be shown.
expression
The expression to be printed.
return
If you would like to capture the output of print_r(), use the return
parameter. When this parameter is set to true
, print_r() will return the information rather than print it.
If given a string, int or float, the value itself will be printed. If given an array, values will be presented in a format that shows keys and elements. Similar notation is used for objects.
When the return
parameter is true
, this function will return a string. Otherwise, the return value is true
.
Note:
When the
return
parameter is used, this function uses internal output buffering so it cannot be used inside an ob_start() callback function.
Example #1 print_r() example
<pre> <?php $a = array ('a' => 'apple', 'b' => 'banana', 'c' => array ('x', 'y', 'z')); print_r ($a); ?> </pre>
The above example will output:
<pre> Array ( [a] => apple [b] => banana [c] => Array ( [0] => x [1] => y [2] => z ) ) </pre>
Example #2 return
parameter example
<?php $b = array ('m' => 'monkey', 'foo' => 'bar', 'x' => array ('x', 'y', 'z')); $results = print_r($b, true); // $results now contains output from print_r ?>
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Licensed under the Creative Commons Attribution License v3.0 or later.
https://www.php.net/manual/en/function.print-r.php