(Go) 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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    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 := StringBuilder_Ref.html">chilkat.NewStringBuilder()
    success = sbScript.LoadFile("js_function_array_arg.js","utf-8")
    if success == false {
        fmt.Println(sbScript.LastErrorText())
        sbScript.DisposeStringBuilder()
        return
    }

    js := Js_Ref.html">chilkat.NewJs()

    result := JsonObject_Ref.html">chilkat.NewJsonObject()
    result.SetEmitCompact(false)

    // Call Eval to add the function to the context's global object
    success = js.Eval(sbScript,result)
    if success == false {
        // Examine the result for an exception.
        fmt.Println(*result.Emit())

        // Also examine the LastErrorText.
        fmt.Println(js.LastErrorText())
        sbScript.DisposeStringBuilder()
        js.DisposeJs()
        result.DisposeJsonObject()
        return
    }

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

    funcCall := JsonObject_Ref.html">chilkat.NewJsonObject()
    funcCall.SetEmitCompact(false)

    // 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.
    argsArray := JsonArray_Ref.html">chilkat.NewJsonArray()

    // The 1st argument in the arguments array is itself an array.
    // Passing -1 indicates to append to the array.
    arg := JsonArray_Ref.html">chilkat.NewJsonArray()
    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)

    fmt.Println(*funcCall.Emit())

    // 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 == false {
        // Examine the result for an exception.
        fmt.Println(*result.Emit())

        // Also examine the LastErrorText.
        fmt.Println(js.LastErrorText())
        sbScript.DisposeStringBuilder()
        js.DisposeJs()
        result.DisposeJsonObject()
        funcCall.DisposeJsonObject()
        argsArray.DisposeJsonArray()
        arg.DisposeJsonArray()
        return
    }

    fmt.Println(*result.Emit())

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

    // The function also emitted text to the console.

    sbOut := StringBuilder_Ref.html">chilkat.NewStringBuilder()
    js.ConsoleOutputSb(sbOut)
    fmt.Println(*sbOut.GetAsString())

    // 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")
    fmt.Println(*funcCall.Emit())

    sbScript.DisposeStringBuilder()
    js.DisposeJs()
    result.DisposeJsonObject()
    funcCall.DisposeJsonObject()
    argsArray.DisposeJsonArray()
    arg.DisposeJsonArray()
    sbOut.DisposeStringBuilder()

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;
}