NSURLSessionConfiguration 对象定义行为和策略使用NSURLSession上载和下载数据时使用目的.上载或下载数据时，创建配置对象始终是您必须采取的第一步.您使用此对象来配置超时值，缓存策略，连接要求以及您打算使用的其他类型的信息与您的 NSURLSession 对象.
An NSURLSessionConfiguration object defines the behavior and policies
to use when uploading and downloading data using an NSURLSession
object. When uploading or downloading data, creating a configuration
object is always the first step you must take. You use this object to
configure the timeout values, caching policies, connection
requirements, and other types of information that you intend to use
with your NSURLSession object.
重要:
注意
在某些情况下，此配置中定义的策略可能是被提供的 NSURLRequest 对象指定的策略覆盖完成一项任务.遵守在请求对象上指定的任何策略除非会议的政策更具限制性.例如，如果会话配置指定不应将蜂窝网络允许， NSURLRequest 对象无法请求蜂窝网络.
In some cases, the policies defined in this configuration may be
overridden by policies specified by an NSURLRequest object provided
for a task. Any policy specified on the request object is respected
unless the session’s policy is more restrictive. For example, if the
session configuration specifies that cellular networking should not be
allowed, the NSURLRequest object cannot request cellular networking.
因此，基本上， NSURLSessionConfiguration 在 NSURLSession 处设置属性，这些属性可以由 NSURLRequest 对象覆盖.
So, essentially, NSURLSessionConfiguration sets the properties at NSURLSession which can be overridden by NSURLRequest object.
这篇关于NSURLSessionConfiguration和NSURLRequest的相同属性?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
