PHP Multudimensional Array foreach - php

Question

Using PHP and MySQL, I have generated an array called $response.
A var_dump of $response can be seen here.
array(2) {
["OperationRequest"]=>
array(4) {
["HTTPHeaders"]=>
array(1) {
[0]=>
array(1) {
["#attributes"]=>
array(2) {
["Name"]=>
string(9) "UserAgent"
["Value"]=>
string(14) "ApaiIO [2.1.0]"
}
}
}
["RequestId"]=>
string(36) "f53f381e-efb3-4fef-8e39-4f732b4b463e"
["Arguments"]=>
array(1) {
["Argument"]=>
array(11) {
[0]=>
array(1) {
["#attributes"]=>
array(2) {
["Name"]=>
string(14) "AWSAccessKeyId"
["Value"]=>
string(20) "KEY"
}
}
[1]=>
array(1) {
["#attributes"]=>
array(2) {
["Name"]=>
string(12) "AssociateTag"
["Value"]=>
string(11) "TAG"
}
}
[2]=>
array(1) {
["#attributes"]=>
array(2) {
["Name"]=>
string(6) "IdType"
["Value"]=>
string(4) "ISBN"
}
}
[3]=>
array(1) {
["#attributes"]=>
array(2) {
["Name"]=>
string(6) "ItemId"
["Value"]=>
string(38) "0751538310,9780141382067,9781305341141"
}
}
[4]=>
array(1) {
["#attributes"]=>
array(2) {
["Name"]=>
string(9) "Operation"
["Value"]=>
string(10) "ItemLookup"
}
}.......so on
A json_encode of the array can be seen here (as requested in a comment).
I'd like to select the Title from these two items. From what I can see this is located at;
Items > Item > ItemAttributes > Author
So, using a foreach loop I have tried the following;
foreach ($response as $item) {
echo $item['Items']['Item']['ItemAttributes']['Title']; // line 2
}
However this returns the following error;
Message: Undefined index: Items. Line Number: 2
Where am I going wrong and what must I change in my code in order to achieve the desired result?
Also, any advice on how to 'read' multidimensional arrays would be greatly appreciated.
Thanks

Answer 1

Try this one, it will help you out. You were are iterating on the wrong key that's why you were not getting desired output.
Try this code snippet herefrom json provide by OP in question
foreach($array["Items"]["Item"] as $key => $value)
{
print_r($value["ItemAttributes"]["Title"]);
echo PHP_EOL;
}
Output:
Panic
Panic
Captain Flinn and the Pirate Dinosaurs: Missing Treasure! (Captain Flinn)
For getting unique titles:
foreach(json_decode($json,true)["Items"]["Item"] as $key => $value)
{
$result[]=$value["ItemAttributes"]["Title"];
echo PHP_EOL;
}
print_r(array_unique($result));

Answer 2

#Also, any advice on how to 'read' multidimensional arrays would be greatly appreciated.
Post your encoded json string to
http://json.parser.online.fr
"+" and "-" button at the right panel should help you read it easily.
//Check Items is not empty
if( !isset($response["Items"]["Item"]) || empty($response["Items"]["Item"]) )
throw New Exception("Empty Item");
foreach($response["Items"]["Item"] as $item){
$title = $item['ItemAttributes']['Title']
}

Answer 3

You should debug as:
foreach ($response as $key => $item) {
if(isset($item['Items'])){ //Check Items index defined
echo $item['Items']['Item']['ItemAttributes']['Title'];
}else{
var_dump($key);
}
}