访问JSON解码为HASH和散列引用数组 [英] Accessing JSON decoded into a HASH and an array of hash references
问题描述
results-> id
记录下的项目。我想能够说出这样的话: print $ results {1342} {'domain'};
,并将结果返回 testing11.com
。
我必须首先阅读所有结果
数组,然后使用 $ results [$ counter] {id}
访问那里的数据?我不知道如何继续。
$ VAR1 = {
'end_time'=> 1466017739,
'options'=> {
'hour_offset'=> '00',
'timezone'=> 'America / New_York'
},
'field_headers'=> {
'priority'=> '优先',
'status'=> '状态',
'assignee_external_id'=> 'Assignee external id',
'initialized_assigned_at'=> '最初分配在'
},
'results'=> [
{
'priority'=> '高',
'status'=> 'open',
'domain'=> 'testing11.com',
'generated_timestamp'=> 1546547669,
'id'=> 1342
},
{
'priority'=> '低',
'status'=> 'open',
'domain'=> 'testing22.com',
'generated_timestamp'=> 1464567669,
'id'=> 7062
},
{
'priority'=> '低',
'status'=> 'closed',
'domain'=> 'testing33.com',
'generated_timestamp'=> 1464267669,
'id'=> 432
}]
}
您的转储显示包含标量,两个哈希值和数组ref的hashref。 arrayref具有元素的hashrefs。如果你想从中检索特定的元素,你需要知道索引。
$ top_level-> {results} - < 0> {domain}; #is'testing11.com'
$ top_level-> {results} - > [0] - > {status}; #是'open'
要迭代,取消引用数组
foreach我的$ result(@ {$ top_level-> {results}}){
print$ result-> {id} \\\
;
}
或者您可以从所有结果
元素的特定键,对于 id
my @ids = map {$ _-> {id}} @ {$ top_level-> {results}};
说@ids;
打印
1342 7062 432
请注意,使用包含引用的嵌套结构还使用语法
$ top_level-> {results} [0] {domain}; #is'testing11.com'
- >
在下标之间是可选的,请参阅在Perlref中使用引用中的规则3.
当哈希键是字符串时,它们应该被引用
$ top_level-> {'results'} [0] {'domain'};
但是,语法快捷方式允许我们省略引号。但是如果在 {}
之内还有其他的内容,它将被解释为表达式并评估。所以如果有任何疑问使用报价。你想要一致的符号。
资源:教程 perlreftut ,参考 perlref 和数据结构cookbook, perldsc 。
解决方案在 stevieb 的答案中给出,创建反向查找。在这里复制参考
我的$ results = $ VAR1-> {results};
我的%by_ip = map {$ _-> {id} => $ _} @ $ results;
打印$ by_ip {1342} - > {domain} \\\
;
Given the following dumper output is there a way to iterate through each hash to list only the items under each results->id
record? I want to be able to say things like:
print $results{1342}{'domain'};
and have the statement return testing11.com
as a result.
Would I have to first read through all of results
array and then use $results[$counter]{id}
to access the data in there ? I'm not sure how to proceed.
$VAR1 = {
'end_time' => 1466017739,
'options' => {
'hour_offset' => '00',
'timezone' => 'America/New_York'
},
'field_headers' => {
'priority' => 'Priority',
'status' => 'Status',
'assignee_external_id' => 'Assignee external id',
'initially_assigned_at' => 'Initially assigned at'
},
'results' => [
{
'priority' => 'High',
'status' => 'Open',
'domain' => 'testing11.com',
'generated_timestamp' => 1546547669,
'id' => 1342
},
{
'priority' => 'Low',
'status' => 'Open',
'domain' => 'testing22.com',
'generated_timestamp' => 1464567669,
'id' => 7062
},
{
'priority' => 'Low',
'status' => 'Closed',
'domain' => 'testing33.com',
'generated_timestamp' => 1464267669,
'id' => 432
}]
}
Your dump shows a hashref containing a scalar, two hashrefs, and an arrayref. The arrayref has hashrefs for elements. If you want to retrieve specific elements from it, you need to know the index.
$top_level->{results}->[0]->{domain}; # is 'testing11.com'
$top_level->{results}->[0]->{status}; # is 'open'
To iterate through it dereference the array
foreach my $result (@{ $top_level->{results} }) {
print "$result->{id}\n";
}
Or you can just get values from all results
elements for a particular key, say for id
my @ids = map { $_->{id} } @{ $top_level->{results} };
say "@ids";
Prints
1342 7062 432
Note that with nested structures, which contain references, you can also use syntax
$top_level->{results}[0]{domain}; # is 'testing11.com'
The ->
is optional between subscripts, see rule 3. in Using References in perlref.
When the hash keys are strings they should be quoted
$top_level->{'results'}[0]{'domain'};
However, a syntax shortcut allows us to omit quotes on barewords. But if there is anything other than a bareword inside {}
it will be interpreted as an expression and evaluated. So if in any doubt use quotes. You want consistent notation throughout.
Resources: Tutorial perlreftut, reference perlref and data structures cookbook, perldsc.
A direct solution is given in stevieb's answer, creating a reverse lookup. Copied here for reference
my $results = $VAR1->{results};
my %by_ip = map {$_->{id} => $_} @$results;
print "$by_ip{1342}->{domain}\n";
这篇关于访问JSON解码为HASH和散列引用数组的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持IT屋!