title: How to convert Hexadecimal NSData to Decimal array?
body: <p>I have an array with hexadecimal value like below:</p>
  
  <pre><code>const UInt8 request_MifareID[] = {
          0x00, 0xCA, 0x01, 0x0A, 0x00
      };
  </code></pre>
  
  <p>then i transfer it to NSData for communication:</p>
  
  <pre><code>NSData *data = [[NSData alloc] initWithBytesNoCopy:(UInt8 *)request_MifareID length:5];
  </code></pre>
  
  <p>Sent "data" to server and get the server response:</p>
  
  <pre><code>Printing description of resp:
  &lt;ee97562d 02280400 00000000 21074400 9000&gt;
  
  NSUInteger len = [resp length];
  
  Printing description of len:
  (NSUInteger) len = 18
  </code></pre>
  
  <p>the "resp" is also a Hexadecimal format NSData</p>
  
  <p>now, i have to transfer the "resp" to Decimal array</p>
  
  <p>how should i do?</p>
  
  <p>------------------------------------------------------Edit</p>
  
  <p>Ok, first</p>
  
  <p>i have to transfer the NSData which server response(it is not String, just numbers):</p>
  
  <pre><code>ee97562d 02280400 00000000 21074400 9000
  </code></pre>
  
  <p>into what kind of object?</p>
  
  <p>Byte?  </p>
  
  <p>when i use </p>
  
  <pre><code>NSString * str = [[NSString alloc] initWithData: resp
                                             encoding:NSUTF8StringEncoding];
  </code></pre>
  
  <p>it returns nil</p>