form_open()

function form_open(string $location, array $attributes = []): string

Description

Generates the opening tag for an HTML form. This is typically the first function called when building a form in Trongate.

Parameters

Parameter	Type	Description
$location	string	The URL or path where the form will be submitted.
$attributes	array	(optional) HTML attributes for the form element. Defaults to an empty array ([]).

Return Value

Type	Description
string	The HTML opening tag for the form.

Example #1: Basic Form

PHP

echo form_open('users/submit');
echo form_input('username', '');
echo form_submit('submit', 'Save');
echo form_close();

// Output:
// <form action="https://example.com/users/submit" method="post">
// <input type="text" name="username">
// <button type="submit" name="submit">Save</button>
// </form>

Example #2: Form with GET Method

PHP

$attributes = [
    'method' => 'get',
    'id' => 'search-form'
];
echo form_open('products/search', $attributes);

// Output:
// <form action="https://example.com/products/search" method="get" id="search-form">

Example #3: Form with Automatic Error Highlighting

PHP

$attributes = [
    'class' => 'highlight-errors'
];
echo form_open('users/register', $attributes);

// Output:
// <form action="https://example.com/users/register" method="post" class="highlight-errors">

Example #4: Trongate MX Form

PHP

$attributes = [
    'mx-post' => 'comments/create',
    'mx-target' => '#comment-list',
    'mx-swap' => 'beforeend'
];
echo form_open('#', $attributes);

// Output:
// <form mx-post="comments/create" mx-target="#comment-list" mx-swap="beforeend" action="#" method="post">

Regarding Trongate MX: When using MX attributes like mx-post, the form submits asynchronously without page reloads. The mx-post attribute takes precedence over the action attribute.

Additional guidance on how to work with Trongate MX is available from the Trongate MX Documentation.

URL Handling

The $location parameter supports different URL formats:

PHP

// Relative path (prepended with BASE_URL)
echo form_open('products/create');
// Output: <form action="https://example.com/products/create" method="post">

// Absolute path
echo form_open('/admin/users');
// Output: <form action="/admin/users" method="post">

// Full URL
echo form_open('https://api.example.com/submit');
// Output: <form action="https://api.example.com/submit" method="post">

Always pair form_open() with form_close() to ensure proper form structure and CSRF protection.
The default method is post. Specify ['method' => 'get'] for GET forms.
For file uploads, use form_open_upload() instead of form_open().
Relative paths are automatically converted to full URLs using the BASE_URL constant.
All attributes are automatically HTML-escaped for security.
The method attribute is handled specially - it's extracted from the attributes array and placed in the proper position.