在命令行上获取用户输入。

Posted 2021-02-27

sub ask {
   my($promptString, $defaultValue) = @_;
 
   if ($defaultValue) {
      print $promptString, "[", $defaultValue, "]: ";
   } else {
      print $promptString, ": ";
   }
 
    $| = 1;               # force a flush after our print
    $_ = <STDIN>;         # get the input from STDIN (presumably the keyboard)
 
   chomp;
 
   if ("$defaultValue") {
      return defined $_ ? $_ : $defaultValue;    # return $_ if it has a value
   }
   return $_;
}