Why are the elements inside "array" changed when I never directly modify it?-CodePudding

The following code changes the elements in the array variable. I would expect changes in sortedArray but it make changes in both. I never have array on the left hand side of any equals sign. I'm never setting array to any value, yet I see changes in it in the debugger when I watch.

static int[] SortArray(int[] array)
{
    int[] sortedArray = array;

    while (!IsSorted(sortedArray))
    {
        for (int i = 0; i < array.Length-1; i  )
        {
            if( sortedArray[i] > sortedArray[i   1])
            {
                sortedArray[i] = array[i   1];
                sortedArray[i   1] = array[i];
            }
        }
    }

    return sortedArray;
}

Before the SortArray method is called, array is (8, 3, 1, 6, 4), and when the method is done, array is (1, 1, 1, 4, 4).

CodePudding user response：

Take a look at the statement int[] sortedArray = array;. With this statement, you're assigning array to sortedArray. Both variables now point to the same array in memory so any change made to it via one of them will also be visible via the other one (since they both point to the same array!).

It seems you meant to copy the array. You could do this by using Array.Copy, or even manually:

int[] sortedArray = new int[array.Length];
for (int i = 0; i < array.Length;   i)
{
    sortedArray[i] = array[i];
}