print_r
(PHP 4, PHP 5, PHP 7)
print_r — Prints human-readable information about a variable
Description
mixed print_r ( mixed $expression [, bool $return = false ] )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 to TRUE, print_r() will return the information rather than print it.
Return Values
If given a string, integer 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
returnparameter 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
← isset
serialize →
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