Perl next 语句用于停止执行从next语句的下一语句开始到循环体结束标识符之间的语句,转去执行continue语句块,然后再返回到循环体的起始处开始执行下一次循环。 语法 语法格式如下所示: next[ LABEL ]; 其中LABEL 是可选的,如果没有指定 LABEL,next 语句将返回到循环体的起始处开始执行下一次循环。 实例 #!/
退出循环为last,与C中的break作用相同;执行下一个循环为next,与C中的continue作用相同;PERL特有的一个命令是redo,其含义是重复此次循环,即循环变量不变,回到循环起始点,但要注意,redo命令在do循环中不起作用。
一般情况下,Perl 程序员偏向于使用 for( ; ; ) 结构来表示一个无限循环。 1.8 循环控制语句 1.8.1 next 语句 next [ LABEL ]; 1. 其中LABEL 是可选的,如果没有指定 LABEL,next 语句将返回到循环体的起始处开始执行下一次循环。 #!/usr/bin/perl $a = 10; while( $a < 20 ){ if( $a == 15...
3、类C的for循环 ,如 for ($count=1; $count <= 5; $count++) { # statements inside the loop go here } 下面是在for循环中使用逗号操作符的例子: for ($line = <STDIN>, $count = 1; $count <= 3; $line = <STDIN>, $count++) { print ($line); } 它等价于下列语句: $line = <S...
DATA_LOOP: foreach my $data (@all_data) { # Forks and returns the pid for the child: mypid =pm->start and next DATA_LOOP; 。。。 方法二: 在perl脚本中指定模块安装路径 #!/usr/bin/perl use strict; use warnings; use lib qw
Past the loop Thenextstops the current iteration and moves on to the next one. This makes it easy to skip elements that you don’t want to process: foreachmy$number (0..5) { say"Starting $number";nextif$number % 2; say"\$number is $number"; ...
用perl编写的snmp采集程序及使用到的产商MIB配置文件 第一部分为snmp的脚本程序，snmp.perl #!/usr/bin/perl ###用户输入设备地址### print"请输入设备地址:"; $DEV_address=<STDIN>; chomp$DEV_address; #print"TheIPis:$DEV_address\n"; ###Ping测试### $Ping_NU=`ping-c2$DEV_address|grep...
\Q Do not look for special pattern characters \t Tab \u Force next letter into uppercase \U All following letters are uppercase \v Vertical tab \L、\U、\Q功能可以由\E关闭掉,如: $a = "T\LHIS IS A \ESTRING"; # same as "This is a STRING" ...
extract_links( ) returns a list of array references, where each array in the list contains a hyperlink mentioned in the HTML. Before we can access the hyperlink returned by extract_links( ), we dereference the list in the for loop: ...
(If you plan to work with years before 1900, add 1900 to $year before the for loop.) Also note that we have to account for leap years, where there are 29 days in February. For the other months, we have prepared an array containing the month lengths. A specific year is a leap ...