在JS中使用AJAX请求跨域时候，会提示错误

Failed to load http://localhost:8889/xxxxxxxxx: No 'Access-Control-Allow-Origin' header is present on the requested resource. Origin 'http://localhost:8085' is therefore not allowed access.

这个是提示服务端没有设置'Access-Control-Allow-Origin'，

以Spring mvc为例

设置Access-Control-Allow-Origin即可，如下：

@RequestMapping(value = "/test",method = RequestMethod.POST)
@ResponseBody
public String test(String param,HttpServletResponse response) {
	response.setHeader("Access-Control-Allow-Origin","*");
	return "test";
}

设置Header值，完成后重启服务，

即可正常访问！