Php/docs/function.print-r
print_r
(PHP 4, PHP 5, PHP 7)
print_r — Prints human-readable information about a variable
Description
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.
Parameters
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 toTRUE
, print_r() will return the information rather than print it.
Return Values
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
.
Notes
Note:
When the
return
parameter is used, this function uses internal output buffering so it cannot be used inside an ob_start() callback function.
Examples
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?>
See Also
- ob_start() - Turn on output buffering
- var_dump() - Dumps information about a variable
- var_export() - Outputs or returns a parsable string representation of a variable