Swift

Call a JavaScript Function Passing an Array Argument

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

func chilkatTest() {
    var success: Bool = 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;
    // }

    let sbScript = CkoStringBuilder()!
    success = sbScript.loadFile(path: "js_function_array_arg.js", charset: "utf-8")
    if success == false {
        print("\(sbScript.lastErrorText!)")
        return
    }

    let js = CkoJs()!

    let result = CkoJsonObject()!
    result.emitCompact = false

    // Call Eval to add the function to the context's global object
    success = js.eval(jscript: sbScript, result: result)
    if success == false {
        // Examine the result for an exception.
        print("\(result.emit()!)")

        // Also examine the LastErrorText.
        print("\(js.lastErrorText!)")
        return
    }

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

    let funcCall = CkoJsonObject()!
    funcCall.emitCompact = false

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

    funcCall.updateString(jsonPath: "name", value: "calculateTotal")

    // Create the arguments array.
    let argsArray = CkoJsonArray()!

    // The 1st argument in the arguments array is itself an array.
    // Passing -1 indicates to append to the array.
    let arg = CkoJsonArray()!
    argsArray.addArrayAt2(index: -1, jarr: arg)

    // Fill in the values for the 1st argument.
    arg.addNumber(at: -1, numericStr: "10.50")
    arg.addNumber(at: -1, numericStr: "20.00")
    arg.addNumber(at: -1, numericStr: "5.25")

    // Add the "args" array to the funcCall.
    funcCall.appendArrayCopy(name: "args", jarr: argsArray)

    print("\(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(func: funcCall, result: result)
    if success == false {
        // Examine the result for an exception.
        print("\(result.emit()!)")

        // Also examine the LastErrorText.
        print("\(js.lastErrorText!)")
        return
    }

    print("\(result.emit()!)")

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

    // The function also emitted text to the console.

    let sbOut = CkoStringBuilder()!
    js.consoleOutputSb(sb: sbOut)
    print("\(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(jsonPath: "name", value: "calculateTotal")
    funcCall.updateNumber(jsonPath: "args[0][0]", numericStr: "10.50")
    funcCall.updateNumber(jsonPath: "args[0][1]", numericStr: "20.00")
    funcCall.updateNumber(jsonPath: "args[0][2]", numericStr: "5.25")
    print("\(funcCall.emit()!)")

}