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# print_r

(PHP 4 )

print_r -- Prints human-readable information about a variable

## Description

bool print_r ( mixed expression)

print_r() displays information about a variable in a way that's readable by humans. 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.

Remember that print_r() will move the array pointer to the end. Use reset() to bring it back to beginning.

> Tip: As with anything that outputs its result directly to the browser, you can use the output-control functions to capture the output of this function, and save it in a string (for example).

    <pre>
    <?php
        $a = array ('a' => 'apple', 'b' => 'banana', 'c' => array ('x','y','z'));
        print_r ($a);
    ?>
    </pre>

Which will output:

    <pre>
    Array
    (
        [a] => apple
        [b] => banana
        [c] => Array
            (
                [0] => x
                [1] => y
                [2] => z
            )
    )
    </pre>

> Note: Prior to PHP 4.0.4, print_r() will continue forever if given an array or object that contains a direct or indirect reference to itself. An example is `print_r($GLOBALS)` because `$GLOBALS` is itself a global variable that contains a reference to itself.

See also ob_start(), var_dump(), and var_export().

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