Kotlin File转ByteArray

方法1：

FileInputStream(this).use { input ->    var offset = 0    var remaining = this.length().toInt()    val result = ByteArray(remaining)    while (remaining > 0) {        val read = input.read(result, offset, remaining)        if (read < 0) break        remaining -= read        offset += read    }    if (remaining == 0) result else result.copyOf(offset)

方法2：

File(path).readBytes()