foreach和数组映射错误

Question

I'm getting: 3 warnings (Illegal offset type in isset or empty in...) 3 notice (Undefined index: ...)

The 3 warnings are realated with the first foreach. And the 3 notices are related with the second foreach loop.

I don't really get what I'm doing wrong... Need some help out here.

<form name="form" action="index.php" method="POST">
    <input type="text" name="name" value="<?php if (isset($_POST['name'])) { echo $_POST['name']; } ?>" />
    <input type="text" name="age" value="<?php if (isset($_POST['age'])) { echo $_POST['age']; } ?>" />
    <input type="text" name="email" value="<?php if (isset($_POST['email'])) { echo $_POST['email']; } ?>" />
    <input type="submit" />
</form>

<?php
$expected = array(
    'name' => array("filter" => FILTER_SANITIZE_STRING),
    'age' => array("filter" => FILTER_SANITIZE_NUMBER_INT),
    'email' => array("filter" => FILTER_SANITIZE_EMAIL)
);

foreach ($expected AS $key => $value) {
    if (!isset($_POST[$value])) {
        echo "not set";
    } elseif (empty($_POST[$value])) {
        echo "empty";
    }
}

$result = filter_input_array(INPUT_POST, $expected);

foreach ($result AS $key => $value) {
    if (!$result[$value]) {
        echo "not valid value";
    }
}
?>

Thank you all.

Answer 1

The forms of foreach are foreach($iterable as $value) and foreach($iterable as $key => $value). There is no foreach ($iterable as $key) form as with javascript's for (key in obj).

Instead use foreach ($expected as $key => $value) { and foreach($result as $key=>$value) { if (!$value) die(false); }

Your complete code should be something like this:

$expected = array(
    'name' => array("filter" => FILTER_SANITIZE_STRING),
    'age' => array("filter" => FILTER_SANITIZE_NUMBER_INT),
    'email' => array("filter" => FILTER_SANITIZE_EMAIL)
);

foreach ($expected AS $key => $value) {
    if (!isset($_POST[$key])) {  // NOT $value!!!!
        echo "not set";
    } elseif (empty($_POST[$key])) {
        echo "empty";
    }
}

$result = filter_input_array(INPUT_POST, $expected);

foreach ($result AS $key => $value) {
    if (!$result[$key]) {  // NOT $value!!!
        echo "not valid value";
    }
}

If your goal is to validate input, then I advise you not make heavy use of the PHP sanitize mechanism. Like all PHP, it is founded on the fundamentally broken philosophy of sanitizing input rather than validating it. I'm not sure what else to advise you to use, however. Respect/Validation looks promising, although I think you would be better off leaving PHP if you can.

Making do with what we have, use the following function with only FILTER_VALIDATE_* filters. You will still need to do pre- and post-processing, and you have to emulate "chained" filters with multiple calls.

function filter_array($data, $filter) {
    $missing = array_diff_key($filter, $data);
    $filtered = filter_var_array($data, $filter);
    $invalid = array_filter($filtered, function($v){return $v===FALSE;});
    $filtered = array_diff_key($filtered, $missing, $invalid);
    return array($filtered, array_keys($invalid), array_keys($missing));
}

Example in use:

$_POST = array('extra'=>'extra', 'age'=>array('30a'), 'name'=>'the name');

$expected = array(
    'name'   => array("filter" => FILTER_UNSAFE_RAW, // using this as a "passthrough" filter
                      "flags"  => FILTER_REQUIRE_SCALAR, // just to set this flag
    ),
    'age'   => array("filter"  => FILTER_VALIDATE_INT,
                     "flags"   => FILTER_REQUIRE_SCALAR,
                     "options" => array('min_range'=>0, 'max_range'=>120)
    ),
    'email' => array("filter"  => FILTER_VALIDATE_EMAIL,
                     "flags"   => FILTER_REQUIRE_SCALAR,
    ),
);

list($valid, $invalid, $missing) = filter_array($_POST, $expected);

var_export($valid); var_export($invalid); var_export($missing);