How would i translate 2 bytes from and to a UShort...

# getting-started

[Sam Smallman]

How would i translate 2 bytes from and to a UShort... I'm sure I'm missing something but functions dealing with Unsigned Integers and multiple bytes seems to be lacking from the standard library.

[stephanmg]

@Sam Smallman I think you look for this: https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/to-u-short.html

[stephanmg]

correct me if I’m wrong

[stephanmg]

vice versa you can go from u-short to byte with toByte()

[stephanmg]

or to unsigned byte with toUByte()

[Sam Smallman]

So a UShort would be 2 bytes right?

[stephanmg]

I think UShort is in Kotlin 16 bits unsigned int

[stephanmg]

https://kotlinlang.org/docs/reference/basic-types.html

[Sam Smallman]

Yeah so i want 2 bytes..

[Kroppeb]

(short >> 8).toUByte()

[stephanmg]

yeah that was what I was thinking

[stephanmg]

does it solve your question @Sam Smallman

[stephanmg]

?

[Sam Smallman]

Not really... I'm receiving a ByteArray via Bluetooth, the data I'm interested in is 6 bytes, the first 2 are a UShort, the last 4 are a UInt, I need to be able to translate them back and forth. Maybe I'm missing something but ideally i want something like .toBytes() which will take a UShort and create two signed bytes..

[Sam Smallman]

or a toByteArray from a UShort i should say..

[Sam Smallman]

and the same for a UInt, and then i can flatten them together.

[Sam Smallman]

ByteBuffer.wrap(data.sliceArray(0 until 2)).short.toUShort()
ByteBuffer.wrap(data.sliceArray(2 until data.size)).int.toUInt()

This is what i have so far...

[Sam Smallman]

and then I've added:

fun Short.toByteArray(): ByteArray {
    return ByteBuffer.allocate(2).putShort(this).array()
}

to go along side Int.toByteArray() to go the other way...

[stephanmg]

well if you receive a ByteArray then why can’t you just convert the first 2 bytes to UShort() and the last 4 to UInt() ?