LWP::UserAgent介绍2

 #这个LWP::UserAgent一般要配合其他模块使用
 #比如:
 #HTTP::Request
 #HTTP::Cookie
 #HTTP::Respose
 #HTTP::Status
 #LWP::UserAgent相当于创建一个模拟浏览器

 #用以下方式创一个浏览器
 my $useragent = LWP::UserAgent->new();
 #一般来说， 我们参数不添加, 到下面要用时再添加， 或让它使用默认值， 它的默认参数如下

 =pod
            KEY                     DEFAULT
            -----------             --------------------
            agent                   "libwww-perl/#.###"
            from                    undef
            conn_cache              undef
            cookie_jar              undef
            default_headers         HTTP::Headers->new
            local_address           undef
            ssl_opts                { verify_hostname =>  }
            max_size                undef
            max_redirect
            parse_head
            protocols_allowed       undef
            protocols_forbidden     undef
            requests_redirectable   ['GET', 'HEAD']
            timeout
 =cut

 如果你想添加参数， 用这种形式:
 my $useragent = LWP::UserAgent->new(agent => 'PERL');
 =pod
 一般来说， 我们不用配置他上面的参数
 当然， 如果你想测试一下， 可以用下面的代码打印一下默认值， 但不一定能正常打印
 =cut

 #!/usr/bin/perl -w
 use strict;
 use LWP::UserAgent;

 my $ua = LWP::UserAgent->new();
 print $ua->agent,"\n";
 print $ua->from,"\n";
 print $ua->conn_cache,"\n";
 print $ua->cookie_jar,"\n";
 print $ua->default_headers,"\n";
 print $ua->local_address,"\n";
 print $ua->ssl_opts,"\n";
 print $ua->max_size,"\n";
 print $ua->max_redirect,"\n";
 print $ua->parse_head,"\n";
 print $ua->protocols_allowed,"\n";
 print $ua->protocols_forbidden,"\n";
 print $ua->requests_redirectable,"\n";
 print $ua->timeout,"\n";

 #可以看到有一些值是要从其他模块去获得的， 像$ua->default_headers, 要从HTTP::Headers->new去构建