Perl | keys()函数
Perl 中的 keys()函数以列表的形式返回 HASH 的所有键。列表中元素的顺序不必总是相同的，但是它与值和每个函数返回的顺序相匹配。
语法:键(HASH)
参数: HASH:要打印其密钥的 HASH
返回:对于标量上下文，它返回散列中的键的数量，而对于列表上下文，它返回键的列表。
例 1:
#!/usr/bin/perl
%hash = ('Ten' => 10,
'Eleven' => 11,
'Twelve' => 12,
'Thirteen' => 13);
@values = values( %hash );
print("Values are ", join("-", @values), "\n");
@keys = keys( %hash );
print("Keys are ", join("-", @keys), "\n");
输出:
Values are 11-12-13-10
Keys are Eleven-Twelve-Thirteen-Ten
例 2:
#!/usr/bin/perl
%hash = ('Geek' => 1,
'For' => 2,
'Geeks' => 3);
@values = values( %hash );
print("Values are ", join("-", @values), "\n");
@keys = keys( %hash );
print("Keys are ", join("-", @keys), "\n");
输出:
Values are 3-2-1
Keys are Geeks-For-Geek
