如何阻止访问某个网站？

上面的理解错了吧；
127.0.0.1 localhost
::1 localhost
这个可以类似DNS的工作；就是解析域名的方式
一般情况，我们用域名访问的话，首先得解析域名；如果hosts存在该域名的话，就不用查询DNS服务来解析，这样可以节约打开网站时间...
如果，你让某个网站的域名解析到错误的IP上，说不定可以；我没试过....不过 ，最简单的方法...防火墙最简单的....；

ts
C:\Windows\System32\drivers\etc
你用记事本就可以打开，内容如下

# Copyright (c) 1993-2006 Microsoft Corp.
#
# This is a sample HOSTS file used by Microsoft TCP/IP for Windows.
#
# This file contains the mappings of IP addresses to host names. Each
# entry should be kept on an individual line. The IP address should
# be placed in the first column followed by the corresponding host name.
# The IP address and the host name should be separated by at least one
# space.
#
# Additionally, comments (such as these) may be inserted on individual
# lines or following the machine name denoted by a '#' symbol.
#
# For example:
#
# 102.54.94.97 rhino.acme.com # source server
# 38.25.63.10 x.acme.com # x client host

127.0.0.1 localhost
::1 localhost

在这里添加你禁止访问的网站就可以了

127.0.0.1 localhost
::1 localhost