Rearrange Array Elements

[code green]

Of all the array functions available in PHP, I cannot find a combination that will fulfill a simple task.
That is move the position of an array element from say column 4 to the first column for an associative array.
Array format

Array{part=>G210, qty_req=>1, stock=>40, Customer=>173053, order_no=>10371482, date=>18-Apr-11}

I wish to become

Array{order_no=>10371482, part=>G210, qty_req=>1, stock=>40, Customer=>173053, date=>18-Apr-11}

What is the most efficient way to do this.
This may be one of a few thousand records within a 2d array extrated from a DB and being written to a CSV

[dlite922]

Try a combination of array_reverse(), array_pop/push() and array_keys().

1. pop the last value
2. pop the last key
3. reverse the array
4. push the value back on to the send
5. reverse the array

All this can be done pretty much on one line of code if you wanted to :)


Dan

[code green]

I can see that will work Dan, in this case.
I was hoping to produce a generic function that could move any column to the first, leaving the other columns in the same place.
It is purely for presentation in a CSV.
The array functions are more efficient that manipulating arrays by hand, but this requires at least 5 function calls, so I doubt it is much better performance.
I think looping and rearranging each row is simpler.

[dlite922]

Well you could design a function that will do exactly that. If I have some free time I'll write it.

Following the rules of programming:

first make it work (function)
then make it elegant (robust)
lastly make it fast. (speed)

I'll do the first, I'm sure you can play around with it and do the other two.

Cheers,



Dan

[dlite922]

see "bdjumakov at gmail dot com" comment on
http://www.php.net/manual/en/function.array-splice.php

Someone might find this function usefull. It just takes a given element from the array and moves it before given element into the same array.

<?php
function array_move($which, $where, $array)
{
    $tmp  = array_splice($array, $which, 1);
    array_splice($array, $where, 0, $tmp);
    return $array;
}
?>

Did that do what you need?



Dan

[code green]

Thanks again Dan.
I had considered array_splice, but as with a lot of the powerful array functions, they don't work with associative arrays.
paule on the same page has written an associative version, that obviously loops through.
I may build from that