perl hash 按value/按keys 排序(多种方法)

use strict;
my%hash=('a'=>2,'b'=>3,'c'=>1);
foreachmy$key(sort{$hash{$b}<=>$hash{$a}}keys%hash){
? ? print$key,"=>",$hash{$key},"n";

}

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"; }