How to Create a PHP Extension Object: Step‑by‑Step Guide

Step 1: Register the class entry

Define a zend_class_entry variable to act as the prototype.

zend_class_entry ce;

Step 2: Set the class name

Use INIT_CLASS_ENTRY to give the class a name and associate its method table.

INIT_CLASS_ENTRY(ce, "children", children_methods);

Step 3: Register the class

Call zend_register_internal_class to obtain a pointer that will be used for later operations.

zend_class_entry *children_ce;
children_ce = zend_register_internal_class(&ce);

Step 4: Declare a property

Declare a public property called memory using the zend_declare_property_null family.

zend_declare_property_null(children_ce, "memory", sizeof("memory")-1, ZEND_ACC_PUBLIC);

Step 5: Define a method

Describe the method signature with ZEND_BEGIN_ARG_INFO_EX and register it in the function entry table.

ZEND_BEGIN_ARG_INFO_EX(arginfo_children_learn, 0, 0, 1)
    ZEND_ARG_INFO(0, love)
ZEND_END_ARG_INFO()

PHP_METHOD(children, learn);

const zend_function_entry children_functions[] = {
    PHP_ME(children, learn, arginfo_children_learn, ZEND_ACC_PUBLIC)
    {NULL, NULL, NULL}
};

Step 6: Implement the method

Parse the incoming string, store it in the memory property, and return.

PHP_METHOD(children, learn)
{
    char *love;
    size_t love_len;

    if (zend_parse_method_parameters(ZEND_NUM_ARGS(), getThis(), "s", &love, &love_len) == FAILURE) {
        return;
    }

    zend_update_property_string(children_ce, getThis(), "memory", sizeof("memory")-1, love);
}

Full extension code

PHP_MINIT_FUNCTION(children)
{
    zend_class_entry ce;
    INIT_CLASS_ENTRY(ce, "children", children_methods);
    children_ce = zend_register_internal_class(&ce);
    zend_declare_property_null(children_ce, "memory", sizeof("memory")-1, ZEND_ACC_PUBLIC);
    return SUCCESS;
}

Using the class from PHP

<?php
$children = new children();
var_dump($children->memory);
$children->learn("love");
var_dump($children->memory);
?>

The output shows NULL for the initial property value and then string(4) "love" after calling learn.