Question

Perl 正则表达式问题

if(/Dia/){/(\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3})/; $dia=$1; $dia=~s/\s+//g; print "dia:$dia\n";}
如果匹配不到数据，就报错
Use of uninitialized value $dia in concatenation (.) or string at sshbroute.pl line 93.
我想匹配不到数据能不能继续执行不报错！

Answer 1

if (/Dia/) {
    if (/(\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3})/) {
        $dia=$1; $dia=~s/\s+//g; 
        print "dia:$dia\n";
    }
}