如何创建可以从外部javascript以及asp.net网站访问的全局变量

Question

在我的网站上，我们有一个通用的javascript，我们将为变量赋值，我想在aspx页面以及另一个javascript文件中调用该变量，有人可以让我知道如何在全局范围内声明这种varibale。

Answer 1

you can write a common javascript file which will contain all the global variable(assuming they are constant and they wont change).

if you have the variable value as non constant, there is noway that you can put it in a javascript file, instead you can use the local storage, cookies to store the information and use it across your javascript files.

the life time of a javascript variable is limited to the page, you navigate to other page its lost.

Answer 2

If you do not expect any page to assign new values in your common javascript, you can add it to the page as the first header script :

<script type="text/javascript" src="script/common.js"></script>

If you want to assign new values and reuse them, it is possible if you let ASP.Net generate your javascript file by passing a query string to the next page's URL, then in that page's script tag. Let's assume that your common variable is called "myGlobalVar". Supposing that "common_js.aspx" dynamically generates your variable definition, you can have something like this :

(URL : www.mysite.com/products.aspx?myGlobalVar=3)

<script type="text/javascript" src="script/common_js.aspx?myGlobalVar=3"></script>

This will keep track of your new js value whenever an update has to be made.

But if so, you may likely want to use a cleaner way to achieve what you want, for example : using the context manager instead of common js vars.