The validator does not require one special request object. Instead, it accepts several useful input shapes and normalises them into a simple key/value structure internally.

That makes it easy to use with plain PHP, with PHP.GT/Input, and with custom request wrappers.

¶Accepted input types

Validator::validate() accepts:

• associative arrays
• iterable objects
• ordinary objects with public properties
• objects that implement an asArray() method

In practice, all of these are valid:

$validator->validate($form, $_POST);

$validator->validate($form, $input);

$validator->validate($form, (object)[
	"email" => "dev@example.com",
	"name" => "Ada Lovelace"
]);

¶Using PHP.GT/Input

If the application uses GT\Input\Input, we can pass it directly:

use GT\Input\Input;

function do_submit(Input $input):void {
	$validator->validate($form, $input);
}

That works because the validator can consume iterable objects and objects that expose array-like request data.

¶Field names must match form names

The validator matches submitted values to inputs by the name attribute.

<input name="email" type="email" required />

$validator->validate($form, [
	"email" => "dev@example.com",
]);

If the field name and the submitted key do not match, the validator will treat the field as empty or missing.

¶Checkbox names with []

Checkbox groups are commonly named like this:

<input type="checkbox" name="interest[]" value="php" />
<input type="checkbox" name="interest[]" value="css" />

The submitted PHP data is usually:

[
	"interest" => ["php", "css"],
]

DomValidation normalises the name attribute by stripping the trailing [] when looking up the submitted input, so this works naturally.

That means:

• DOM name: interest[]
• submitted key: interest

¶Multiple values

If the submitted value is an array, the validator converts each entry to a string internally.

That is mainly useful for checkbox groups and other repeated field names.

¶Object input

If an object is passed in, the validator checks it in this order:

1. if it has an asArray() method, that is used
2. if it is traversable, it is converted with iterator_to_array()
3. otherwise its public properties are read

Non-scalar object properties are treated as empty strings.

This allows simple request DTOs to work without extra mapping glue.

¶A practical rule

Keep the submitted structure close to what the HTML form actually emits.

That way:

• required checks behave as expected
• checkbox arrays stay grouped correctly
• custom rules that inspect other fields are easier to write

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Once the input is accepted and validation fails, the next useful topic is Understanding validation errors.