Remove element of a regular array

Question

If you don't want to use List:

var foos = new List<Foo>(array);
foos.RemoveAt(index);
return foos.ToArray();

You could try this extension method that I haven't actually tested:

public static T[] RemoveAt<T>(this T[] source, int index)
{
    T[] dest = new T[source.Length - 1];
    if( index > 0 )
        Array.Copy(source, 0, dest, 0, index);

    if( index < source.Length - 1 )
        Array.Copy(source, index + 1, dest, index, source.Length - index - 1);

    return dest;
}

And use it like:

Foo[] bar = GetFoos();
bar = bar.RemoveAt(2);

The nature of arrays is that their length is immutable. You can't add or delete any of the array items.

You will have to create a new array that is one element shorter and copy the old items to the new array, excluding the element you want to delete.

So it is probably better to use a List instead of an array.

I use this method for removing an element from an object array. In my situation, my arrays are small in length. So if you have large arrays you may need another solution.

private int[] RemoveIndices(int[] IndicesArray, int RemoveAt)
{
    int[] newIndicesArray = new int[IndicesArray.Length - 1];

    int i = 0;
    int j = 0;
    while (i < IndicesArray.Length)
    {
        if (i != RemoveAt)
        {
            newIndicesArray[j] = IndicesArray[i];
            j++;
        }

        i++;
    }

    return newIndicesArray;
}

LINQ one-line solution:

myArray = myArray.Where((source, index) => index != 1).ToArray();

The 1 in that example is the index of the element to remove -- in this example, per the original question, the 2nd element (with 1 being the second element in C# zero-based array indexing).

A more complete example:

string[] myArray = { "a", "b", "c", "d", "e" };
int indexToRemove = 1;
myArray = myArray.Where((source, index) => index != indexToRemove).ToArray();

After running that snippet, the value of myArray will be { "a", "c", "d", "e" }.