Perl

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. Perl

use chilkat();

$success = 0;

# This is the JavaScript function we'll call:

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

$sbScript = chilkat::CkStringBuilder->new();
$sbScript->Append("function describeCar(car) { console.log(`This is a ${car.year} ${car.make} ${car.model}.`); }");

$js = chilkat::CkJs->new();

$result = chilkat::CkJsonObject->new();
$result->put_EmitCompact(0);

# Call Eval to add the function to the context's global object
$success = $js->Eval($sbScript,$result);
if ($success == 0) {
    # Examine the result for an exception.
    print $result->emit() . "\r\n";

    # Also examine the LastErrorText.
    print $js->lastErrorText() . "\r\n";
    exit;
}

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

$funcCall = chilkat::CkJsonObject->new();
$funcCall->put_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.
$arg = chilkat::CkJsonObject->new();
$arg->UpdateString("make","Toyota");
$arg->UpdateString("model","Corolla");
$arg->UpdateInt("year",2022);

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

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

print $funcCall->emit() . "\r\n";

$success = $js->CallFunction($funcCall,$result);
if ($success == 0) {
    # Examine the result for an exception.
    print $result->emit() . "\r\n";

    # Also examine the LastErrorText.
    print $js->lastErrorText() . "\r\n";
    exit;
}

print $result->emit() . "\r\n";

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

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

# However, the function emitted text to the console.

$sbOut = chilkat::CkStringBuilder->new();
$js->ConsoleOutputSb($sbOut);
print $sbOut->getAsString() . "\r\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() . "\r\n";