javascript - 如何在纯 JavaScript 中稍微修改变量函数？

Question

所以我们有这样的事情：

var variable1 = 1;
var variable2 = 2;

var doSomething = function() {
    alert(variable1 + ' ' + variable2);
}; // After this initialization, the content of that variable is completely hidden from the programmer's eyes.

doSomething(); // 1 2

// How to modify doSomething to update **`variable2`** to 3?

doSomething(); // ...Would like to modify doSomething to be able to output 1 3

是否可以将doSomething其variable2部分更新为新值？

如果我们需要在变量中重新创建函数doSomething，它必须来自存储的信息doSomething而不是硬编码。

标签： javascriptfunctionvariables

Answer 1

使 variable2 成为可选参数：

var variable1 = 1;
var variable2 = 2;

var doSomething = function(v2 = variable2) {
    alert(variable1 + ' ' + v2);
};

doSomething(3);