# TestBufferWriterStruct.Advance(int)

[Type overview](/orleans/docs/api/csharp/microsoft.orleans.serialization.testkit/orleans.serialization.testkit.testbufferwriterstruct/) | [Methods](/orleans/docs/api/csharp/microsoft.orleans.serialization.testkit/orleans.serialization.testkit.testbufferwriterstruct/methods/)

[Source](https://github.com/dotnet/orleans/blob/e4e752cedecc2976811db49802c7a999b1f1c704/src/Orleans.Serialization.TestKit/TestBufferWriterStruct.cs#L21)

```csharp
public void Advance(int bytes)
```

Notifies the `System.Buffers.IBufferWriter-1` that `count` data items were written to the output `System.Span-1` or `System.Memory-1`.

### Parameters

- `bytes` (`int`): The number of data items written to the `System.Span-1` or `System.Memory-1`.