Is there any simple way to concatenate two BitArray (C# .NET)?

Question

I have

var previous = new BitArray(new bool[]{true});
var current = new BitArray(new bool[]{false});

I want to concatenate them. I have already tried:

var next = new BitArray(previous.Count + current.Count);
var index = 0;
for(;index < previous.Count; index++)
    next[index] = previous[index];
var j = 0;
for(;index < next.Count; index++, j++)
    next[index] = current[j];
previous = current;

But it doesn't look like the best way to do it.

Answer 1

Unfortunately it looks like your method might be as good as it gets - if BitArray implemented IEnumerable<T> (instead of just IEnumerable) then we could use LINQ extension methods to make it a bit prettier.

If I were you, I'd wrap this up into an extension method on BitArray:

public static BitArray Prepend(this BitArray current, BitArray before) {
    var bools = new bool[current.Count + before.Count];
    before.CopyTo(bools, 0);
    current.CopyTo(bools, before.Count);
    return new BitArray(bools);
}

public static BitArray Append(this BitArray current, BitArray after) {
    var bools = new bool[current.Count + after.Count];
    current.CopyTo(bools, 0);
    after.CopyTo(bools, current.Count);
    return new BitArray(bools);
}