Validator

Client-side form validation with inline error messages, blur/input triggers, and built-in rules. Prevents layout shifts by using Manhattan styling instead of native HTML5 validation.

Registration Form Example

Fill out the form and submit to see validation...

// Attach a validator to any form by its ID.
// Flag rules are plain strings; value rules are single-key arrays.
<?= $m->validator('myForm')
    ->field('username', 'Username is required',        ['required'])
    ->field('email',    'Valid email required',          ['required', 'email'])
    ->field('password', 'Min 8 characters',             ['required', ['minLength' => 8]])
    ->field('bio',      'Max 200 characters',           [['maxLength' => 200]])
    ->field('score',    'Must be between 0 and 100',    [['min' => 0], ['max' => 100]])
    ->field('code',     'Alphanumeric codes only',      ['required', ['pattern' => '^[a-zA-Z0-9]+$']])
    ->onSubmit('handleSubmit(event)')
    ->validateOnBlur()
    ->validateOnInput() ?>

// onSubmit fires only when all fields pass
function handleSubmit(event) {
    event.preventDefault();
    var data = new FormData(event.target);
    console.log('Valid form submitted', Object.fromEntries(data));
}

// JS validation rules reference:
// Flag rules (plain strings):
//   'required'   — must not be empty
//   'email'      — valid email format
//   'integer'    — whole number
//   'positive'   — number > 0
//
// Value rules (single-key array in PHP → object in JS config):
//   ['minLength' => 5]          → {minLength: 5}
//   ['maxLength' => 200]        → {maxLength: 200}
//   ['min' => 0]                → {min: 0}
//   ['max' => 100]              → {max: 100}
//   ['pattern' => '^[a-z]+$']  → {pattern: '^[a-z]+$'}
//   ['custom' => fn]            → {custom: function(value, input) { return true; }}

PHP PHP Methods (Fluent)

Method / Property	Parameters	Description
`$m->validator($formId)`	`string`	Create a validator targeting the form with the given ID.
`->field($name, $message, $rules)`	`string, string, array`	Add a field to validate. Flag rules are plain strings (`'required'`, `'email'`); value rules are single-key arrays (`['minLength' => 8]`, `['pattern' => '^\.+$']`).
`->onSubmit($callback)`	`string`	JS code to execute when the form passes all validation.
`->validateOnBlur($enabled)`	`bool`	Validate fields when they lose focus (default: true).
`->validateOnInput($enabled)`	`bool`	Validate fields in real-time on each keystroke (default: false).

JS JS Validation Rules

Method / Property	Parameters	Description
`required`		Field must have a non-empty value.
`email`		Value must be a valid email address.
`minLength`	`int`	Minimum string length.
`maxLength`	`int`	Maximum string length.
`min`	`number`	Minimum numeric value.
`max`	`number`	Maximum numeric value.
`integer`		Value must be a whole number.
`positive`		Value must be a positive number.
`pattern`	`string (regex)`	Value must match the given regex pattern.
`custom`	`function(value, input)`	Custom validation function returning true/false.