1.删除之前安装的PHP
yum remove php* php-common
2.安装yum源
rpm -Uvh https://dl.fedoraproject.org/pub/epel/epel-release-latest-7.noarch.rpm
rpm -Uvh https://mirror.webtatic.com/yum/el7/webtatic-release.rpm
3.安装PHP7
yum clean all
yum install php70w.x86_64 php70w-cli.x86_64 php70w-common.x86_64 php70w-fpm.x86_64 php70w-gd.x86_64 php70w-mbstring.x86_64 php70w-mcrypt.x86_64 php70w-pdo.x86_64 php70w-pecl-xdebug.x86_64
4.测试一下
php -v
5.重启apache
service httpd restart
6.修改php.ini后，用下面的命令让配置生效
service php-fpm restart