How can I convert a zero-terminated byte array to string?

go
Derrick Zhang picture Derrick Zhang · Jan 9, 2013 · Viewed 492.4k times · Source

I need to read [100]byte to transfer a bunch of string data.

Because not all of the strings are precisely 100 characters long, the remaining part of the byte array is padded with 0s.

If I convert [100]byte to string by: string(byteArray[:]), the tailing 0s are displayed as ^@^@s.

In C, the string will terminate upon 0, so what's the best way to convert this byte array to string in Go?

Answer

Daniel picture Daniel · Jan 9, 2013

Methods that read data into byte slices return the number of bytes read. You should save that number and then use it to create your string. If n is the number of bytes read, your code would look like this:

s := string(byteArray[:n])

To convert the full string, this can be used:

s := string(byteArray[:len(byteArray)])

This is equivalent to:

s := string(byteArray)

If for some reason you don't know n, you could use the bytes package to find it, assuming your input doesn't have a null character embedded in it.

n := bytes.Index(byteArray, []byte{0})

Or as icza pointed out, you can use the code below:

n := bytes.IndexByte(byteArray, 0)

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