How can the serialized size of EventData be determ

In the documentation for the Azure EventHubClient there are two methods for sending a batch of data each of them has the remark below and will throw a MessageSizeExceededException if it is ignored.

You should ensure that the total serialized size of eventDataList is less than the size limit of one event data transmission, which is 256k by default.

A similar warning is present in the Programming Guide

How can the serialized size of IEnumerable<EventData> eventDataList be determined?

The size of the bytes passed to each EventData is easy enough to determine, assuming you don't ask the EventData. However, the serialized form of an EventData presumably includes the Partition Key and user properties as used in the sample.

data.Properties.Add("Type","Telemetry_" + DateTime.Now.ToLongTimeString());

Currently my only option looks like being conservative with batch sizing.

----Updating after the Nuget Update---- Here's the EventData property - SerializedSizeInBytes that we introduced in our recent SDK iteration - which addresses this specific problem - available in all sdk nugets above 2.6 .

---Update after EventDataBatch utility---

use EventDataBatch.TryAdd(EventData) API to construct the batch. When the EventData cannot fit into the batch - this API will return false. Stop adding more events & then use the sender (EventHubClient or PartitionSender) to send the EventDataBatch.

following considerations motivated us to design EventDataBatch API:

Help developers using our Client API - to deal with size of batch of EventData
Abstract out region-wide/SKU-based MaximumMessageSize configuration: EventHubs service across the world could have different Max EventData sizes - across different EventHub regions and different SKUs of EventHub. We wanted to expose a uniform way for developers to construct maximum message size for any given environment. So, when EventDataBatch is initialized using eventHubClient.createBatch() API - the client negotiates batchSize with EventHubs Service and returns the EventDataBatch instance which can construct the correct size!