在数组的开头插入一个键值对在 php 中

Question

array_unshift ($ids,$product_id => $catalog_tag);

if i put

array($product_id => $catalog_tag) 

would work but wont add $product_id as key.. I want to add it at the start

Answer 1

Use array_reverse to reverse the array and then push the element to end of array using array_push and then reverse the array again. You will have the new element at beginning of the array.

or

$arrayone=array("newkey"=>"newvalue") + $arrayone; 

Answer 2

This code takes your array noting that it's using integer keys for your array so these will always be the array order, so we convert them to string keys and this prevents the key's acting as the order of the array. we then create the a new array with your value and append all values from your existing array to the end.

note that the product ID is converted to a string again to prevent the integer key from ordering the array.

$ids = array(0 => "bla bla", 1 => "bla bla", 2 => "bla bla", 3 => "bla bla")
foreach($ids as $key => $val){
    $key = "$key";
}
unset(current($ids));
$ids = array_merge(array("$product_id" => $catalog_tag), $ids);

Answer 3

See this answer.

It refers to moving an already existing element to the beginning of the array, but it would also have the desired result if it doesn't exist.