语法结构

语法:        if (condition) {...};
默认值:    -
上下文:    server location
示例:        
        if($http_user_agent ~ Chrome){
              rewrite /(.*) /browser/$1 break;
        }

condition

配置段演示

server {
    listen 8080;
    # 请求域名无限制
      #server_name ~.*;
    server_name localhost www.ngserver1.com 192.168.58.8 192.168.58.9;
    root html;
    location /search/ {
        if ( $remote_addr = "192.168.58.1" ) { # 访问用户的ip地址
        return 200 "test if OK in URL /search/";
        } 
    }
  
    # break 知识点
      # nginx/html/pics/index.html
    location / {
        if ( $uri = "/images/" ) {
        rewrite (.*) /pics/ break;
        }
        # 即使if条件成立return还是会执行,因为此时 rewrite同return 不是同级指令
        return 200 "test if failed\n";
    }
    location /test/ {        
    }
}
curl 192.168.58.8:8080/images/