Perl Requires Chilkat v11.4.0+

Call a JavaScript Function Passing an Array Argument

See more JavaScript Examples

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

use strict;
use warnings;
use Chilkat2;

# This is the JavaScript function we'll call:

# function calculateTotal(numbers) {
#   console.log(numbers);
#   let total = 0;
#
#   // Loop through every number in the array
#   for (const num of numbers) {
#     console.log(num);
#     total += num;
#   }
#
#   return total;
# }

my $sbScript = Chilkat2::StringBuilder->new;
my $success = $sbScript->LoadFile('js_function_array_arg.js', 'utf-8');
if (!$success) {
    print $sbScript->LastErrorText, "\n";
    exit;
}

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
$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 calculateTotal(numbers)

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 array.

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

# Create the arguments array.
my $argsArray = Chilkat2::JsonArray->new;

# The 1st argument in the arguments array is itself an array.
# Passing -1 indicates to append to the array.
my $arg = Chilkat2::JsonArray->new;
$argsArray->AddArrayAt2(-1, $arg);

# Fill in the values for the 1st argument.
$arg->AddNumberAt(-1, '10.50');
$arg->AddNumberAt(-1, '20.00');
$arg->AddNumberAt(-1, '5.25');

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

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

# The funcCall is as follows.  Notice that the 1st (and only) argument is an array.

# {
#   "name": "calculateTotal",
#   "args": [
#     [
#       10.50,
#       20.00,
#       5.25
#     ]
#   ]
# }

$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";

# Result:
# {
#   "type": "double",
#   "value": 35.75
# }

# The function also emitted text to the console.

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

# Output:
# 10.5,20,5.25
# 10.5
# 20
# 5.25

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

$funcCall->Clear();
$funcCall->UpdateString('name', 'calculateTotal');
$funcCall->UpdateNumber('args[0][0]', '10.50');
$funcCall->UpdateNumber('args[0][1]', '20.00');
$funcCall->UpdateNumber('args[0][2]', '5.25');
print $funcCall->Emit(), "\n";

JavaScript

function calculateTotal(numbers) {
  console.log(numbers);
  let total = 0;
  
  // Loop through every number in the array
  for (const num of numbers) {
    console.log(num);
    total += num;
  }
  
  return total;
}