perl中如何将按hash key值排序

如果是按ASCII码排序，则代码如下：

foreach my $key ( sort { $hash{$a} cmp $hash{$b} } keys %hash ) {     my $value = $hash{$key}; # do something with ($key,$value) }

如果是按数字小到大排列，则代码如下：

foreach my $key ( sort { $hash{$a} <=> $hash{$b} } keys %hash ) {      my $value = $hash{$key};      #do something with ($key,$value) }

 

如果是按数字大到小排列，则代码如下：

foreach my $key ( sort { $hash{$b} <=> $hash{$a} } keys %hash ) {      my $value = $hash{$key};      #do something with ($key,$value) }

 

按KEY排列

foreach my $item (sort {$a<=>$b} keys %hash){ print "$item  == > $hash{$item}","/n";}