print_r
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 thereturn
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
← isset
serialize →
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Licensed under the Creative Commons Attribution License v3.0 or later.