Prints human-readable information about a variable
Syntax
print_r(mixed $value, bool $return = false): string|bool
Parameters
value
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
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.
Examples
1 · value · bool
<? $value = false; print_r($value); ?>
2 · value · int
<? $value = 0; print_r($value); ?>
0
3 · value · float
<? $value = 0.0; print_r($value); ?>
0
4 · value · string
<? $value = "0"; print_r($value); ?>
0
5 · value · array
<? $value = array(0, 1, array(0, 1)); print_r($value); ?>
Array ( [0] => 0 [1] => 1 [2] => Array ( [0] => 0 [1] => 1 ) )
6 · value · object · standard class
<? $value = new stdclass; $value->var = 0; print_r($value); ?>
stdClass Object ( [var] => 0 )
7 · value · object · custom class
<? class myclass { public $var; } $value = new myclass; $value->var = 0; print_r($value); ?>
myclass Object ( [var] => 0 )
8 · return · false
<? class myclass { public $var; } $value = new myclass; $value->var = 0; $return = false; $output = print_r($value, $return); echo "output: " . PHP_EOL; var_export($output); ?>
myclass Object ( [var] => 0 ) output: true
9 · return · true
<? class myclass { public $var; } $value = new myclass; $value->var = 0; $return = true; $output = print_r($value, $return); echo "output: " . PHP_EOL . $output; ?>
output: myclass Object ( [var] => 0 )