Order an array using another array as indexes C#

Question

Hi,

so if I have an array of characters

char[] chars = new char[]{'f','a','d','e','c','b'};

and another array of integers that say what the sort order is:

int[] sortOrder = new int[]{5,1,4,5,3,2};

how could I sort the data in the chars array, using the values in the sortOrder array to determine the order? In the above example, the sorted array would look like

{'a','b','c','d','e','f'}

(the 'd' moved to position 4, the 'a' to position 1, etc. Where the 5 is repeated, the order doesn't matter.)

I know I could do it by creating a third array, but ideally I would like to do it using LinQ (the .Sort) method or something similar, because there may be duplicated values in the sortOrder array.

I guess effectively I want to sort the sortOrder array (easy using sortOrder.Sort()), but then get it to sort the chars array with the exact same changes, somehow?

Answer 1

There is an overload of Array.Sort that does exactly that...

Array.Sort(sortOrder, chars);

(note that this actually sorts both arrays in parallel - i.e. it sorts the keys, and makes the same swaps to the target array)