新手：关于perl的if循环

cherzx

我是个新手，最近在看小骆驼，因为我是一边看一边巧代码玩，perl的if循环问题请求指教：
print "please input date:";
chomp ($today = <STDIN>);
if ( $today eq monday ){
print "Today is $today\n";
print "you should learn 1111\n";
}
if ( $today eq Tuesday ){
print "Today is $today\n";
print "you should  learn  2222\n";
}
if ( $today eq wednesday ){
print "Today is $today\n";
print "you should learn 3333\n";
}
else {
print "please input data\n";
}
因为我以前都是用linux下的shell，我觉得当我输入monday的时候，只会输出print "Today is $today\n";
print "you should learn 1111\n";
但是事实是连else的结果也同时print了呢？？？
怎么写才能让它值匹配其中的一个啊？？？

Perlvim

如果你希望所有的条件只能满足一个，在多个条件下，要用：
if (boolean exp) { exp }
elsif (boolean exp) { exp }
else { exp }

if (boolean exp) { exp }
if (boolean exp) { exp }
else { exp }
的格式，会检查所有的 if 项目

另外你这里明显有语法错误。

$today eq monday 中的 monday 应当用引号标记为一个字符串，不能用裸字写，除非你先声明成一个常量。
应当这样写：$today eq 'monday'

xudongxu27

print "please input date:";
chomp ($today = <STDIN>);
if ( $today eq "monday" ){
print "Today is $today\n";
print "you should learn 1111\n";
}
elsif ( $today eq "Tuesday" ){
print "Today is $today\n";
print "you should  learn  2222\n";
}
elsif ( $today eq "wednesday" ){
print "Today is $today\n";
print "you should learn 3333\n";
}
else {
print "please input data\n";
}