Perl Requires Chilkat v11.4.0+

Call a JavaScript Function Passing an Object Argument

See more JavaScript Examples

Demonstrates how to call a JavaScript function with an argument that is an object. Chilkat2 Perl

use strict;
use warnings;
use Chilkat2;

# This is the JavaScript function we'll call:

# function describeCar(car) {
#     console.log(`This is a ${car.year} ${car.make} ${car.model}.`);
# }

my $sbScript = Chilkat2::StringBuilder->new;
$sbScript->Append('function describeCar(car) { console.log(`This is a ${car.year} ${car.make} ${car.model}.`); }');

my $js = Chilkat2::Js->new;

my $result = Chilkat2::JsonObject->new;
$result->EmitCompact(0);

# Call Eval to add the function to the context's global object
my $success = $js->Eval($sbScript, $result);
if (!$success) {
    # Examine the result for an exception.
    print $result->Emit(), "\n";

    # Also examine the LastErrorText.
    print $js->LastErrorText, "\n";
    exit;
}

# ------------------------------------------------------------------------------
# Call the function describeCar(car)

my $funcCall = Chilkat2::JsonObject->new;
$funcCall->EmitCompact(0);

# Create JSON specifying the function name and arguments
# In this case, there is only 1 argument, and it is an object.

# {
#   "name": "describeCar",
#   "args": [
#     {
#       "make": "Toyota",
#       "model": "Corolla",
#       "year": 2022
#     }
#   ]
# }

$funcCall->UpdateString('name', 'describeCar');

# Create the JSON object that is the argument.
my $arg = Chilkat2::JsonObject->new;
$arg->UpdateString('make', 'Toyota');
$arg->UpdateString('model', 'Corolla');
$arg->UpdateInt('year', 2022);

# Create the arguments array.
my $argsArray = Chilkat2::JsonArray->new;
$argsArray->AddObjectCopyAt(0, $arg);

# Add the "args" array to the funcCall.
$funcCall->AppendArrayCopy('args', $argsArray);

print $funcCall->Emit(), "\n";

$success = $js->CallFunction($funcCall, $result);
if (!$success) {
    # Examine the result for an exception.
    print $result->Emit(), "\n";

    # Also examine the LastErrorText.
    print $js->LastErrorText, "\n";
    exit;
}

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

# The describeCar JavaScript function returns nothing.
# Therefore, the result is "undefined".

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

# However, the function emitted text to the console.

my $sbOut = Chilkat2::StringBuilder->new;
$js->ConsoleOutputSb($sbOut);
print $sbOut->GetAsString(), "\n";

# Output:
# This is a 2022 Toyota Corolla.

# -----------------------------------------------------------
# Note: If the object argument is simple, this is an alternative
# and simpler way of creating the funcCall:

$funcCall->Clear();
$funcCall->UpdateString('name', 'describeCar');
$funcCall->UpdateString('args[0].make', 'Toyota');
$funcCall->UpdateString('args[0].model', 'Corolla');
$funcCall->UpdateInt('args[0].year', 2022);
print $funcCall->Emit(), "\n";