# ReadOnlyDictionaryCodec<TKey, TValue>.ConvertToSurrogate(ReadOnlyDictionary<TKey, TValue>, ReadOnlyDictionarySurrogate<TKey, TValue>)

[Type overview](/orleans/docs/api/csharp/microsoft.orleans.serialization/orleans.serialization.codecs.readonlydictionarycodec-2/) | [Methods](/orleans/docs/api/csharp/microsoft.orleans.serialization/orleans.serialization.codecs.readonlydictionarycodec-2/methods/)

[Source](https://github.com/dotnet/orleans/blob/e4e752cedecc2976811db49802c7a999b1f1c704/src/Orleans.Serialization/Codecs/ReadOnlyDictionaryCodec.cs#L19)

```csharp
public override void ReadOnlyDictionaryCodec<TKey, ConvertToSurrogate(ReadOnlyDictionary<TKey, TValue> value, ref ReadOnlyDictionarySurrogate<TKey, TValue> surrogate)
```

Converts a value to the surrogate type.

### Parameters

- `value` (`ReadOnlyDictionary<TKey, TValue>`): The value.
- `surrogate` (`ReadOnlyDictionarySurrogate<TKey, TValue>`): The surrogate.