Array Slice in C#


Unfortunately the array objects in C# do not have functions to return parts of them and I think it is not efficient to use Linq extension functions (in these cases). That is the reason why I have created a convenient Slice extension function:



public static class ArrayExtensions
{
//returns a part of the source array
public static T[] Slice<T>(this T[] source, int start, int end)
{
    int count = end - start + 1;
    T[] target = null;
    if (count > 0)
    {
        target = new T[count];
        for (int i = start; i <= end; i++)
            target[i - start] = source[i];
    }
    return target;
}
}

Here is an example, that shows to you the usage of the generic Slice function:

string[] linesSrc, lineTo;
...
//return a sub-array of the first three elements of the linesSrc array
lineTo = linesSrc.Slice<string>(0, 2);

That's the good part of the extension functions: it is general and can be used for all type of arrays.

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