title: How to get PartitionId in event hub triggered Azure function?
body: <p>I have an Azure Function triggered by Event Hub. I configured the function app in the host.json with a MaxBatchSize of 32. My Event Hub has 6 partitions, and I don't want an event to be processed twice.</p>
  
  <p>So, I need partition ID and sequence number to identify the event uniquely. I would like to save PartitionID and SequenceNumber in my database as primary keys. My function is triggered in input with Array of EventData. Iterating on the array, I can get the SequenceNumber for each message, but I don't know how to get per PartitionID. I tried to include parameter of type PartitionContext among input parameters but it doesn't work.  </p>
  
  <p>Here it is my code: </p>
  
  <pre class="lang-cs prettyprint-override"><code>[FunctionName("EventHubTriggeredFunction")]
  public static void Run([EventHubTrigger("events", Connection = "EventHubConnection")]EventData[] eventHubMessages, TraceWriter log)
  {
      foreach (var message in eventHubMessages)
      {
          using (Stream stream = message.GetBodyStream())
          {
              using (StreamReader reader = new StreamReader(stream))
              {
                  try
                  {
                      //... do something
  
                      //SequenceNumber: message.SequenceNumber
                      Save(reader.ReadToEnd(), message);
  
                      //... do something else
                  }
              }
          }
   }
  </code></pre>
  
  <p>How can I get PartitionID for each message processed?</p>