是否可以有两个具有相同名称的不同变量? [英] Is it possible to have two different variables with the same name?

问题描述

在jQuery中是否可以有两个具有相同名称的不同变量?

Is it possible to have two different variables in with the same name in jQuery?

我的jQuery链接到外部脚本.可以有两个使用相同字母名称的变量吗?

I have my jQuery linking to outside scripts. Is it possible to have two variables using the same letter name?

即:

包含在compressed.js中:

Contained in compressed.js:

var m = $$('li', s),

和

包含在 http://www.google.com/jsapi :

var m = "push",

这两个相互影响吗?

推荐答案

简单的答案是否"，它们不会互相影响.

The simple answer is no, they will not effect each other.

它的工作方式是每个变量名都是唯一的，因此m，m1，m2，m3，m4彼此之间没有任何影响:

how it works is that each variable name is unique, so m,m1,m2,m3,m4 does not have any affect to each other what so ever:

但是，根据设置为变量的值，您可以像这样访问和更改数据m[2]的原因是m是数组或某种对象，并且可以通过以下方式访问各个元素使用[]可能会使您感到困惑.

However depending on the value set to the variable you may access and change data like so m[2] the reason for this is that m is an array or an object of some kind, and you can access the individual elements by using the [] which is probably where your getting confused.

变量如何相互影响的示例:

Example of how variables effect eachother:

var a = 'hello';
var b = 'world';

alert(a); //hello
alert(b); //world

alert(a + b); //helloworld
alert(b + a); //worldhello

a = b;

alert(a); //world
alert(b); //world

b = 'hey';

alert(b); //hey

从上面的示例中可以看到，

如果修改已经设置的变量的值，如果尚未设置该变量的赋值，它将更改该值；

as you can see from the examples above if you modify the value of a variable that has already been set it changes the value, if the variable has not already been set its assigned the value;

一个不错的技巧，您应该学习自调用匿名函数，我们使用它们的原因是创建一个将代码放入其中的框，这样它不会影响框外的任何其他事物.

a nice trick that you should learn self calling anonymous functions, the reason we use these is to create a box to put our code inside so it does not effect anything else outside the box.

示例

var hey = 'hey';

(function(){
    var hey = 'bye'; //This is only effective inside the {}

    alert(hey); //You get 'bye';

    //Access the global scope
    alert(window.hey); //You get 'hey';

    //modifiy the external scope
    window.hey = 'modified from within the function';

    //expose vars inside the function scope to the global window:
    window.exposed = hey; //Remember hey is internal and is set to 'bye';
})();

alert(exposed); //'bye';
alert(hey); //'modified from within the function'

希望您现在了解更多

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