(C) Call a JavaScript Function Passing an Array Argument

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Note: This example requires Chilkat v11.4.0 or greater.

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#include <C_CkStringBuilder.h>
#include <C_CkJs.h>
#include <C_CkJsonObject.h>
#include <C_CkJsonArray.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkStringBuilder sbScript;
    HCkJs js;
    HCkJsonObject result;
    HCkJsonObject funcCall;
    HCkJsonArray argsArray;
    HCkJsonArray arg;
    HCkStringBuilder sbOut;

    success = FALSE;

    // 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;
    // }

    sbScript = CkStringBuilder_Create();
    success = CkStringBuilder_LoadFile(sbScript,"js_function_array_arg.js","utf-8");
    if (success == FALSE) {
        printf("%s\n",CkStringBuilder_lastErrorText(sbScript));
        CkStringBuilder_Dispose(sbScript);
        return;
    }

    js = CkJs_Create();

    result = CkJsonObject_Create();
    CkJsonObject_putEmitCompact(result,FALSE);

    // Call Eval to add the function to the context's global object
    success = CkJs_Eval(js,sbScript,result);
    if (success == FALSE) {
        // Examine the result for an exception.
        printf("%s\n",CkJsonObject_emit(result));

        // Also examine the LastErrorText.
        printf("%s\n",CkJs_lastErrorText(js));
        CkStringBuilder_Dispose(sbScript);
        CkJs_Dispose(js);
        CkJsonObject_Dispose(result);
        return;
    }

    // ------------------------------------------------------------------------------
    // Call the function calculateTotal(numbers)

    funcCall = CkJsonObject_Create();
    CkJsonObject_putEmitCompact(funcCall,FALSE);

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

    CkJsonObject_UpdateString(funcCall,"name","calculateTotal");

    // Create the arguments array.
    argsArray = CkJsonArray_Create();

    // The 1st argument in the arguments array is itself an array.
    // Passing -1 indicates to append to the array.
    arg = CkJsonArray_Create();
    CkJsonArray_AddArrayAt2(argsArray,-1,arg);

    // Fill in the values for the 1st argument.
    CkJsonArray_AddNumberAt(arg,-1,"10.50");
    CkJsonArray_AddNumberAt(arg,-1,"20.00");
    CkJsonArray_AddNumberAt(arg,-1,"5.25");

    // Add the "args" array to the funcCall.
    CkJsonObject_AppendArrayCopy(funcCall,"args",argsArray);

    printf("%s\n",CkJsonObject_emit(funcCall));

    // 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 = CkJs_CallFunction(js,funcCall,result);
    if (success == FALSE) {
        // Examine the result for an exception.
        printf("%s\n",CkJsonObject_emit(result));

        // Also examine the LastErrorText.
        printf("%s\n",CkJs_lastErrorText(js));
        CkStringBuilder_Dispose(sbScript);
        CkJs_Dispose(js);
        CkJsonObject_Dispose(result);
        CkJsonObject_Dispose(funcCall);
        CkJsonArray_Dispose(argsArray);
        CkJsonArray_Dispose(arg);
        return;
    }

    printf("%s\n",CkJsonObject_emit(result));

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

    // The function also emitted text to the console.

    sbOut = CkStringBuilder_Create();
    CkJs_ConsoleOutputSb(js,sbOut);
    printf("%s\n",CkStringBuilder_getAsString(sbOut));

    // 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:

    CkJsonObject_Clear(funcCall);
    CkJsonObject_UpdateString(funcCall,"name","calculateTotal");
    CkJsonObject_UpdateNumber(funcCall,"args[0][0]","10.50");
    CkJsonObject_UpdateNumber(funcCall,"args[0][1]","20.00");
    CkJsonObject_UpdateNumber(funcCall,"args[0][2]","5.25");
    printf("%s\n",CkJsonObject_emit(funcCall));


    CkStringBuilder_Dispose(sbScript);
    CkJs_Dispose(js);
    CkJsonObject_Dispose(result);
    CkJsonObject_Dispose(funcCall);
    CkJsonArray_Dispose(argsArray);
    CkJsonArray_Dispose(arg);
    CkStringBuilder_Dispose(sbOut);

    }

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;
}