How can I insert (not replace) a byte at zero inde...

# getting-started

[Oleh Ponomarenko]

How can I insert (not replace) a byte at zero index in ByteArray ?

[dalexander]

Assuming the existing array is already full: Make a new ByteArray with length equal to your current ByteArray + 1. Use System.arrayCopy() to copy the existing ByteArray into the new ByteArray starting at index 1. Set index 0 equal to your new value. Note that if performance is a concern you probably want to figure out a way to avoid doing this operation.

[Dico]

Instead of System.arraycopy (which will work) you should use oldArray.copyInto which is available in the kotlin stdlib on all platforms.

[Dico]

On the other hand, the easy dirty way would be to use
val newArray = byteArrayOf(elemToAdd, *oldArray).