Perl语言引用常用方法总结

# 標量

my $var = "wangchao";

my $var_ref = \$var;

print ${$var_ref} . "\n"; # wangchao

${$var_ref} = "zhansan";

print ${$var_ref} . "\n"; # zhansan

print $var . "\n";        # zhansan

# 列表

my @list;

push @list, "wangchao";

push @list, "mahan";

print "@list" . "\n";        # wangchao mahan

my $list_ref = \@list;

print "@{$list_ref}" . "\n"; # wangchao mahan

push @{$list_ref}, "zhanglong";

print "@list" . "\n";        # wangchao mahan zhanglong

print "@{$list_ref}" . "\n"; # wangchao mahan zhanglong

# 哈希

my %hash;

$hash{1} = "wangchao";

$hash{2} = "mahan";

# 以下輸出wangchaomahan

foreach (keys %hash) {

print $hash{$_};

}

print "\n";

my $hash_ref = \%hash;

$hash_ref->{3} = "zhanglong";

# 以下輸出wangchaozhanglongmahan

foreach (keys %hash) {

print $hash{$_};

}

print "\n";

# 以下輸出wangchaozhanglongmahan

foreach (keys %{$hash_ref}) {

print $hash_ref->{$_};

}

print "\n";

# 標量、列表、哈希引用作為參數

sub foo

{

$foo_var_ref = $_[0];

$foo_list_ref = $_[1];

$foo_hash_ref = $_[2];

print ${$foo_var_ref} . "\n";    # zhansan

print "@{$foo_list_ref}" . "\n"; # wangchao mahan zhanglong

# wangchaozhanglongmahan

foreach (keys %{$foo_hash_ref}) {

print $foo_hash_ref->{$_};

}

}

# 調用函數

&foo(\$var, \@list, \%hash);