Table of Contents
1 数组的数组
1.1 创建和访问二维数组
创建是最简单的，举例：
1: @AoA = (["fruit","ball"], 2: ["home","bart","marge"], 3: ["george","jane","elory"]); 4: print $AoA[2]->[1]; 5: #每一对相邻的大括号或中括号之间有一个隐含的->,所以也可以这样写 6: print $AoA[2][1]; 7: 8: #整个列表被封装在小括号中，而不是中括号中，因为是给列表赋值， 9: #而不是给引用赋值，如果要创建一个指向数组的引用，那么你要这样 10: $ref_to_AoA =[ ["fred","barney","pebbles","bamm"], 11: ["homer","bart","marge","maggie",] 12: ]; 13: print $ref_to_AoA->[2][3]; 14: #注意这里有在中括号前面的箭头符号。因为这是引用，所以要在前面加上-> 15: 16: #还有一点就是可以利用负数索引从数组后面向前计数， 17: $AoA[0][-2]; 18: #表示第一行的倒数第二个元素
1.2 自行生长
我们读入一个数据结构，是一个纯文本文件，每一行是一个结构的一行，并且没行 包含由空白分割的元素。
1: while(<>) 2: { 3: chomp; 4: @tmp = split; 5: push @AoA,[@tmp]; 6: } 7: #或者直接不用命名那个数组 8: while(<>) 9: { 10: push @AoA, [split]; 11: } 12: #如果想要引用指向一个数组的数组，可以这样 13: while(<>) 14: { 15: push @ref_to_AoA,[split]; 16: } 17: #如果要向数组中增加列，还是使用简单的赋值 18: #如果向一个存在的行中附加一个新列 19: push @{@AOA[0]},"wilma","betty"; 20: #注意push的参数必须以@开头
1.3 访问和打印
1: #单元素打印 2: print $AoA[3][2]; 3: #遍历整个数组 4: for $now (@AoA) 5: { 6: print "@$row\n"; 7: } 8: #如果你想追踪脚标 9: for $i (0..$#AoA) 10: { 11: print "row $i is:@{$AoA[$i]}\n"; 12: } 13: #或者 14: for $i (0..$#AoA) 15: { 16: for $j (0..$#{$AoA[$i]}) 17: { 18: print "element $i $j is $AoA[$i][$j]\n"; 19: } 20: } 21: #为了简化上面的程序，我们可以使用临时变量，让事情变的简单。 22: for $i (0..$#AoA) 23: { 24: $row = $AoA[$i]; 25: for $j (0..$@{$row}) 26: { 27: print "element $i $j is $row->[$j]\n"; 28: } 29: }
1.4 片段
如果要访问一个多维数组的某一片段的元素，你可以用循环把变量一个个的取出来。
1: @part = (); 2: for ($y = 7 ;$y <13 ;$y++) 3: { 4: push @part,$AoA[4][$y]; 5: } 6: #这个循环可以用一个数组片段来替代 7: @part = @{$AoA[4]} [7..12]; 8: #如果要一个二维片段，同样也可以通过循环来获得 9: #也可以用上面刚学到的方法 10: for ($x=4;$x<=9;$x++) 11: { 12: push @new_AoA,[@{$AoA[$x]} [7..12]]; 13: } 14: #如果你经常这么做，可以写一个子程序，或者到CPAN上下载一个 15: #PDL（perl data language)模块
2 数组的散列
关于这个名称，我们可以这样理解，数组的散列是由“数组”组成的散列， 我们可以首先可以根据散列的key快速找到数组，然后再访问数组。
2.1 数组的散列的组成
1: %HoA = ( flintstones =>["fred","barney"], 2: jetsons =>["george","jane","elroy"], 3: ); 4: #向散列增加另一个数组 5: $HoA{teletubbies} = ["tinky","dispay","laa",];
2.2 生成数组的散列
从下面格式的文件中读取： flintsotnes: fred barney wilma dino
jetsons: george jane elroy
simpsons: homer marge bart
下面是填充数组的散列的技巧
1: while(<>) 2: { 3: next unless s/^(.*?):\s*//; 4: $HoA{$i}=[split]; 5: } 6: #或者 7: while($line = <>) 8: { 9: ($who,$rest)=split/:\s*/,$line,2; 10: @fields=split ' ',$rest; 11: $HoA{$who}=[@fields]; 12: } 13: #可以通过一下方法向已存在的数组追加新的成员 14: push @{$HoA{flintstones}},"wilma","pebbles";
2.3 访问和打印数组
打印所有的元素
1: for $family (keys %HoA) 2: { 3: print "$family: @{$HoA{$family}}\n"; 4: } 5: #你可以为数组增加索引 6: for $family (keys %HoA) 7: { 8: print "$family: "; 9: for $i (0..$#{$HoA{$family}}) 10: { 11: print " $i = $HoA{$family}[$i]"; 12: } 13: print "\n"; 14: } 15: #或者通过以数组拥有的元素个数对他们排序 16: for $family (sort {@{$HoA{$b}} <=> @{$HoA{$a}}} keys %HoA) 17: { 18: print "$family: @{$HoA{$family}}\n"; 19: } 20: #也可以以元素的个数对数组排序，然后以元素的ASCII码顺序进行排序 21: for $family (sort {@{$HoA{$b}}<=>@{$HoA{$a}}} keys %HoA) 22: { 23: print "$family: ",join(",",sort @{$HoA{$family}}),"\n"; 24: }
3 散列的数组
这个名称和上一个名称容易混淆，散列的数组，就是由“散列“组成的”数组“， 我们的本意是对一堆数据，想要按照顺序访问他们。并且每一个记录后面又 包含key/value对
3.1 散列的数组的组成。
1: @AoH = ({husband => "barney", 2: wife => "betty", 3: son => "bamm", 4: }, 5: {husband => "george", 6: wife => "jane", 7: son => "elroy", 8: }, 9: {husband => "homer", 10: wife => "marge", 11: son => "bart", 12: }, 13: ); 14: 15: 16: #向数组中添加另外一个散列， 17: push @AoH,{husband => "fred",wife => "wilma",daughter=>"pebbles"};
3.2 生成散列的数组
从文件中读取下面的格式
husband=fred friend=barney
1: while(<>) 2: { 3: $rec = {}; 4: for $field (split) 5: { 6: ($key,$value) = split/=/,$field; 7: $rec->{$key} = $value; 8: } 9: push @AoH,$rec; 10: } 11: 12: #或者用下面更简单的方法 13: while(<>) 14: { 15: push @AoH,{split /[\s=]+/}; 16: } 17: 18: #可以向下面这样向一个现存的散列添加新成员 19: $AoH[0]{pet} = "dino"; 20: $AoH[2]{pet} = "santa's";
3.3 访问和打印散列的数组
用下面的方法设置一个特定散列的键/值对
1: $AoH[0]{husband} = "fred"; 2: #把第二个数组的丈夫变成大写 3: $AoH[1]{husband} = ~s/(\w)/\u$1/; 4: 5: #打印所有数据的方法： 6: for $href (@AoH) 7: { 8: print "{ "; 9: for $role (keys %$href) 10: { 11: print "$role=$href->{$role}"; 12: } 13: print "}\n"; 14: } 15: 16: #带着索引打印 17: for $i (0..$#AoH) 18: { 19: print "$i is {"; 20: for $role (keys %{$AoH[$i]}) 21: { 22: print "$role=$AoH[$i]{$role} "; 23: } 24: print "}\n"; 25: }
4 散列的散列
多维散列是Perl中最灵活的嵌套结构。
4.1 散列的散列的组成
1: %HoH=( 2: flintstones=> 3: { 4: husband => "fred", 5: pal => "barney", 6: }, 7: jetsons => 8: { 9: husband => "george", 10: wife => "jane", 11: "his boy" => "elroy", 12: }, 13: simpsons => 14: { 15: husband => "homer", 16: wife => "marge", 17: kid => "bart", 18: }, 19: ); 20: #向%HoH中增加一个匿名散列 21: $HoH{mash} = { 22: captain => "pierce", 23: major => "burns", 24: corporal=> "radar", 25: }
4.2 生成散列的散列
从下面格式的文件中读取数据：
1: flintstones: husband=fred pal=barney wife=wilma pet=dino
我们可以使用下面两个循环之一来完成任务
1: while(<>) 2: { 3: next unless s/^(.*?):\S*//; 4: $who = $1; 5: for $field (split) 6: { 7: ($key,$value)=split/=/,$field; 8: $HoH{$who}{$key} = $value; 9: } 10: } 11: 12: #或者 13: while(<>) 14: { 15: next unless s/^(.*?):\S*//; 16: $who = $1; 17: $rec = {}; 18: $HoH{$who} = $rec; 19: for $field (split) 20: { 21: ($key,$value）= split/=/,$field; 22: $rec->{$key}= $value; 23: } 24: }
4.3 访问和打印散列的散列
1: #设置键/值对 2: $HOH{flintstones}{wife} = "wilma"; 3: 4: #要把某个键/值对变成大写，可对该元素应用替换 5: $HoH{jetsons}{'his boy'} =~s/(\w)/\u$1/; 6: 7: #打印所有的元素，利用先后遍历内外层散列键的方法 8: for $family (keys %HoH) 9: { 10: print "$family: "; 11: for $role (keys %{$HoH{$family}}) 12: { 13: print "$role = $person "; 14: } 15: print "\n"; 16: } 17: 18: #在非常大的散列中，可以用each同时把键和值都检索出来 19: while (($family,$roles) = each %HoH) 20: { 21: print "$family: "; 22: while (($role,$person) = each %$roles) 23: { 24: print "$role = $person"; 25: } 26: print "\n"; 27: } 28: 29: #排序输出 30: for $family (sort keys %HoH) 31: { 32: print "$family: "; 33: for $role (sort keys %{$HoH{$family}}) 34: { 35: print "$role=$HoH{$family}{$role} "; 36: } 37: print "\n"; 38: }
5 函数的散列
6 以上内容摘自大骆驼，谢谢
Date: 2013-05-31 19:22:49 CST
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