How to separate two array by id - php

Question

I have an array ,i want to seperate array into single array by there TNXID.by any php function seperate array by TXNID into one single array variable .Because i want to save array with parent TXNID and child TXNID save..My demo code is
Array
(
[XYX] => Array
(
[0] => Array
(
[TXNObjectType] => 102
[CustomerAccountID] => 951
[ParentTXNLineNumber] => 1
[TXNID] => 11
)
[1] => Array
(
[TXNObjectType] => 84
[CustomerAccountID] => 951
[ParentTXNLineNumber] => 1
[TXNID] => 12
)
)
[XYZ] => Array
(
[0] => Array
(
[TXNID] => 11
[LineNo] => 7
[BranchID] => 164
)
[1] => Array
(
[TXNID] => 11
[LineNo] => 8
[BranchID] => 164
)
[2] => Array
(
[TXNID] => 12
[LineNo] => 9
[BranchID] => 164
)
[3] => Array
(
[TXNID] => 12
[LineNo] => 10
[BranchID] => 164
)
)
)
Expected output:
Array(
Array
(
[XYX] => Array
(
[0] => Array
(
[TXNObjectType] => 102
[CustomerAccountID] => 951
[ParentTXNLineNumber] => 1
[TXNID] => 11
)
)
)
Array(
[XYZ] => Array
(
[0] => Array
(
[TXNID] => 11
[LineNo] => 7
[BranchID] => 164
)
[1] => Array
(
[TXNID] => 11
[LineNo] => 8
[BranchID] => 164
)
)
)
Array(
Array
(
[XYX] => Array
(
[0] => Array
(
[TXNObjectType] => 102
[CustomerAccountID] => 951
[ParentTXNLineNumber] => 1
[TXNID] => 12
)
)
)
Array(
[XYZ] => Array
(
[0] => Array
(
[TXNID] => 12
[LineNo] => 7
[BranchID] => 164
)
[1] => Array
(
[TXNID] => 12
[LineNo] => 8
[BranchID] => 164
)
)
)
so please suggest mi appropriate solution for this .

Answer 1

I will try to give you an approach on how I would go about it. Here you need to take care of two keys while rearranging the nested arrays. First is the outer-most keys labelled XYX,XYZ and so on. Second is the key for the child array i.e. TXNID.
So, initially you could traverse the array and transform(flatten) it into this form:
Array
( [0] => Array
(
[TXNObjectType] => 102
[CustomerAccountID] => 951
[ParentTXNLineNumber] => 1
[TXNID] => 11
[Parent] => XYX //Store the parent at the same level
)
[1] => Array
(
[TXNObjectType] => 84
[CustomerAccountID] => 951
[ParentTXNLineNumber] => 1
[TXNID] => 12
[Parent] => XYX //Store the parent at the same level
)
...
Once you have this, you could simply sort this array of arrays based on the key TXNID. For that you might want to use uasort. You will have to define a custom comparator for this, should be a fun exercise.
Once you have sorted the array of arrays. You will just have to traverse this array one last time and sort of uncompress it, by checking the Parent key and pushing in array elements with that as the key and the sorted arrays as the values to get back a nested output like you desire.
There several other array functions in PHP that might come in handy. This might not even be the most efficient solutions but I hope it gets you started in the right direction.