Than the Switch… Case more elegant multi-condition judgment writing

preface

A few days ago, I was responsible for the preparation of the website online environmental judgment function, which involves a large number of multi-condition judgment code. For multi-conditional writing, most programmers use if… else if… Or else the switch… Case, but there is a more interesting and elegant multi-condition method than the traditional one — object attribute method.

Examples show

Without further ado, the following direct use of three examples, to show you three different multi-conditional judgment writing methods.

1. if... else if... else

function whatFood(mealtime) {
    let food = ' ';

    if (mealtime === 'breakfasttime') {
        food = 'egg';
    } else if (mealtime === 'lunchtime') {
        food = 'vegetable'
    } else if (mealtime === 'dinnertime') {
        food = 'fruit'
    } else {
        food = 'cookie'
    }

    return food;
}
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2. switch... case

function whatFood(mealtime) {
    let food = ' ';

    switch (mealtime) {
        case 'breakfasttime':
            food = 'egg';
            break;
        case 'lunchtime':
            food = 'vegetable';
            break;
        case 'dinnertime':
            food = 'fruit';
            break;
        default:
            food = 'cookie';
    }

    return food;
}
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3. Object attribute judgment method

function whatFood(mealtime) {

    const food = {
        breakfasttime: 'egg',
        lunchtime: 'vegetable',
        dinnertime: 'fruit'
    }

    return food[mealtime] ? food[mealtime] : 'cookie';
}
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conclusion

I believe you have seen the advantages and disadvantages of different writing methods through the above three examples. If you have a better multi-conditional writing method, please leave a comment and discuss it. Wish you a smooth work and a happy life.