39、现代 JavaScript 特性详解

现代 JavaScript 特性详解

1. 函数参数处理：ES5 与 ES6 的对比

在处理函数参数时，ES5 和 ES6 有明显的差异。以下是一个计算税收的示例：

// ES5 版本
function calcTaxES5(income) {
    var customers = Array.prototype.slice.call(arguments, 1);
    console.log("ES5. Calculating tax for customers with the income " + income);
    customers.forEach(function (customer) {
        console.log("Processing ", customer);
    });
}

calcTaxES5(50000, "Smith", "Johnson", "McDonald");
calcTaxES5(750000, "Olson", "Clinton");

// ES6 和剩余参数运算符
function calcTaxES6(income, ...customers) {
    console.log(`ES6. Calculating tax for customers with the income ${income}`);
    customers.forEach((customer) => console.log(`Processing ${customer}`));
}

calcTaxES6(50000, "Smith", "Johnson", "McDona