问题解决了，不仅是服务器要配置而且.htaccess也要配置
<IfModule mod_rewrite.c>
Options +FollowSymlinks -Multiviews
RewriteEngine On
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME} !-f
RewriteRule ^api/?(.*)$ api.php?s=$1 [QSA,PT,L]
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME} !-f
RewriteRule ^(.*)$ index.php?s=$1 [QSA,PT,L]
</IfModule>