javascript中的静态数组变量？

Question

Can I create an static variable as array in javascript, What I want to do is to keep the value static even when refreshing the page.

I'm trying now is create a function as object like:

function Data(p){
    Data.point.push(p);
    Data.size++;
}
Data.size = 0; 
Data.point = [];

But then I noticed every time I refresh the page, it will reset the Data because of the last two lines.

Answer 1

您可以使用sessionStorage在页面刷新期间保留数据。

Answer 2

No javascript data is preserved from one page load to the next. The entire javascript context of a page is destroyed when a new page is loaded over the top of it.

Your options for saving state that survives a page load are as follows:

1. Save the data in LocalStorage so future web pages can read it from there.
2. Save the data in a cookie so future web pages can read it from there.
3. Save the data on your server so it can be loaded into future pages automatically or so future web pages can query the server with ajax.
4. Encode the data into a queryString and use that URL when reloading the page, then parsing the data out of the queryString when the new page loads.

Of all of these, the LocalStorage option is probably the simplest and cleanest. You can read about it here: https://developer.mozilla.org/en-US/docs/Web/Guide/API/DOM/Storage#localStorage

LocalStorage (or session storage if you want a shorter lifetime for the storage) is available in IE8 and above and all other popular browsers. The MDN article referenced above even includes a shim that will fallback to cookies if LocalStorage is not supported (eg old versions of IE).