Javascript cross-origin solution (1)

1. Shenma is a cross-domain (CrossDomain). The white point is post, and the get url is not your current website. The domain name is different. For example, in aaa.com/a.html, the table Ticket delivery action is bbb.com/ B .html. In addition, www.aaa.com and aaa.com are also cross-domain, because www... S

 

1. Shenma is a Cross-Domain)

The white point is that the post and get URLs are not your current website, and the domain names are different. For example, in aaa.com/a.html, the table Ticket delivery action is bbb.com/ B .html.

In addition, www.aaa.com and aaa.com are also cross-domain because www.aaa.com is a second-level domain name and aaa.com is a root domain name.

For security reasons, JavaScript does not allow cross-Origin calls to objects on other pages (Same-Origin Policy ).

For a detailed description of whether JavaScript can communicate across regions, see the following table:

Http://www.a.com/a.jsAccess the following URL results

URL	Description	Allow communication?
Http://www.a.com/ B .js	Under the same domain name	Allow
Http://www.a.com/script/ B .js	Different folders under the same domain name	Allow
Http://www.a.com: 8000/B. js	Different ports for the same domain name	Not Allowed
Https://www.a.com/ B .js	Different protocols for the same domain name	Not Allowed
Http: // 70.32.92.74/B. js	Corresponding ip addresses of domain names and domain names	Not Allowed
Http://script.a.com/ B .js	The primary domain is the same and the subdomain is different.	Not Allowed
Http://a.com/ B .js	Same domain name, different second-level domain names (same as above)	Not Allowed
Http://www. B .com/ B .js	Different domain names	Not Allowed

 

2. Why cross-origin?

Cross-origin is actually very common. For example, we can place some scripts, images, or other resources of a website on another site. For example, we can use jQuery provided by Google, which reduces loading time and server traffic, as shown below: