Check out example codes for "add values to array dynamically php". It will help you in understanding the concepts better.
Code Example 1
There are quite a few ways to work with dynamic arrays in PHP. Initialise an array: $array = array(); Add to an array: $array = "item"; // for your $arr1 $array[$key] = "item"; // for your $arr2 array_push($array, "item", "another item"); Remove from an array: $item = array_pop($array); $item = array_shift($array); unset($array[$key]); There are plenty more ways, these are just some examples.
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