title: Byte array in objective-c
body: <p>How can I create a byte array in Objective-C?</p>
  
  <p>I have some data like this:<code>0x12, 0x23, 0x34, 0x45, 0x56, 0x67, 0x78, 0x89, 0x12, 0x23, 0x34, 0x45, 0x56, 0x67, 0x78, 0x89</code>, that I want to prepare as a byte array.</p>