(Go) Call a JavaScript Function Returning a Boolean

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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 isEven(number) {
    //     return number % 2 === 0;
    // }

    sbScript := StringBuilder_Ref.html">chilkat.NewStringBuilder()
    sbScript.Append("function isEven(number) { return number % 2 === 0; }")

    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 isEven(8)

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

    // Create JSON specifying the function name and arguments

    // {
    //   "name": "isEven",
    //   "args": [ 8 ]
    // }

    funcCall.UpdateString("name","isEven")
    funcCall.UpdateInt("args[0]",8)

    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()
        return
    }

    fmt.Println(*result.Emit())

    // Output:
    // {
    //   "type": "bool",
    //   "value": true
    // }

    retval := result.BoolOf("value")
    fmt.Println(retval)

    // Output:
    // true

    sbScript.DisposeStringBuilder()
    js.DisposeJs()
    result.DisposeJsonObject()
    funcCall.DisposeJsonObject()