未捕獲的引用錯誤：（函數）未定義 JAVASCRIPT

Question

const markProperties = {
    fullName: 'Mark Miller',
    mass: 78,
    height: 1.69,
        calcBMI: function () {
        return this.mass / this.height ** 2;
    },
    bmi: calcBMI()



    


}

const johnProperties = {
    fullName: 'John Smith',
    mass: 92,
    height: 1.95,

    calcBMI: function () {
        this.bmi = this.mass / this.height ** 2;
        return this.bmi;
    },
    bmi: calcBMI()
};

const checkWinner = () => {
    if (johnProperties.bmi > markProperties.bmi) {
        return "John's BMI (" + johnProperties.bmi + ") is higher than Mark's BMI (" + markProperties.bmi + ")";
    } else if (markProperties.bmi > johnProperties.bmi) {
        return "Mark's BMI (" + markProperties.bmi + ") is higher than John's BMI (" + johnProperties.bmi + ")";
    }
}
console.log(checkWinner());

這是代碼，它表示未定義兩個對象中的 function。 正如我所說，它帶來了一個錯誤，內容如下：錯誤：未捕獲的引用錯誤：未定義 calcBMI

Answer 1

當您定義 object 時，您不能執行在 object 中定義的 function。在您的情況下，您應該簡單地為bmi屬性設置一個 getter：

 const markProperties = { fullName: 'Mark Miller', mass: 78, height: 1.69, get bmi() { return this.mass / this.height ** 2; } } const johnProperties = { fullName: 'John Smith', mass: 92, height: 1.95, get bmi() { return this.mass / this.height ** 2; } }; const checkWinner = () => { if (johnProperties.bmi > markProperties.bmi) { return "John's BMI (" + johnProperties.bmi + ") is higher than Mark's BMI (" + markProperties.bmi + ")"; } else if (markProperties.bmi > johnProperties.bmi) { return "Mark's BMI (" + markProperties.bmi + ") is higher than John's BMI (" + johnProperties.bmi + ")"; } } console.log(checkWinner());