PHP Requires Chilkat v11.4.0+

Call a JavaScript Function Returning an Integer

See more JavaScript Examples

Demonstrates how to call a JavaScript function that returns an integer. Chilkat2 PHP

<?php

use Chilkat2\Js;
use Chilkat2\JsonObject;
use Chilkat2\StringBuilder;

// ----------------------------------------------------------------------------------
// The Javascript function called in this example is shown at the bottom of this page.
// -----------------------------------------------------------------------------------

// In this example, we'll load the Javascript function definition from a file.
// It doesn't need to come from a file.  It could just as easily be loaded from a string.
$sbScript = new StringBuilder();
try {
    $sbScript->LoadFile('js_call_function.js', 'utf-8');
} catch (\Chilkat2\Exception $e) {
    echo $e->getMessage(), "\n";
    exit;
}

// Note: Each instance of a Chilkat Js object automatically establishes
// its own internal runtime and context.  Applications do not need to explicitly create
// the JavaScript runtime or context.
$js = new Js();

$result = new JsonObject();
$result->EmitCompact = false;

// Call Eval to add the function (shown at the bottom of this page) to the context's global object
try {
    $js->Eval($sbScript, $result);
} catch (\Chilkat2\Exception $e) {
    // Examine the result for an exception.
    echo $result->Emit(), "\n";

    // Also examine the LastErrorText.
    echo $e->getMessage(), "\n";
    exit;
}

echo $result->Emit(), "\n";

// The expected output is "undefined":

// {
//   "type": "undefined",
//   "value": "undefined"
// }

//    When Eval processes a script containing only a function declaration,
//    it successfully performs the action (the function becomes defined).
//    However, since the script consists of a statement that produces no value,
//    the script's overall completion value is empty. In JavaScript, the
//    absence of a value is represented by `undefined`.
//
//    Therefore, the Eval call returns `undefined`.

// ------------------------------------------------------------------------------
// Call the function calculateScore("Player1", 10, 20)

$funcCall = new JsonObject();

// Create JSON defining the function call:

// {
//   "name": "calculateScore",
//   "args": [ "Player1", 10, 20 ]
// }

$funcCall->UpdateString('name', 'calculateScore');
$funcCall->UpdateString('args[0]', 'Player1');
$funcCall->UpdateInt('args[1]', 10);
$funcCall->UpdateInt('args[2]', 20);

$funcCall->EmitCompact = false;
echo $funcCall->Emit(), "\n";

try {
    $js->CallFunction($funcCall, $result);
} catch (\Chilkat2\Exception $e) {
    // Examine the result for an exception.
    echo $result->Emit(), "\n";

    // Also examine the LastErrorText.
    echo $e->getMessage(), "\n";
    exit;
}

echo $result->Emit(), "\n";

// Output:

// {
//   "type": "int",
//   "value": 37
// }

$retval = $result->IntOf('value');
echo 'retval = ', $retval, "\n";

JavaScript

function calculateScore(name, pointsA, pointsB) {
    // Return length of name + both scores
    return name.length + pointsA + pointsB;
    }