Can I use JsonSerializerOptions to customize error handling in MvvmCross

Using `JsonSerializerOptions` for Custom Error Handling in MvvmCross

While `JsonSerializerOptions` is primarily used with `System.Text.Json` for configuring serialization and deserialization settings, it does not directly handle errors in the same way that `Newtonsoft.Json` does. However, you can leverage `JsonSerializerOptions` to customize serialization settings that might indirectly affect error handling by avoiding certain serialization issues.

Customizing Serialization Settings

In `System.Text.Json`, you can configure `JsonSerializerOptions` to handle specific serialization scenarios, such as setting property naming policies or handling null values. However, for error handling, you would typically catch exceptions thrown during serialization or deserialization, such as `JsonException` or `NotSupportedException`[3][6].

Handling Exceptions in MvvmCross

For handling exceptions in MvvmCross, you typically use a combination of base view models and error reporting mechanisms. Here's how you can approach it:

1. Base ViewModel for Shared Error Handling: Create a base view model class that includes methods for handling exceptions. This can include logging errors or displaying them to the user[2][5].

2. Error Reporting Mechanism: Implement an error reporting mechanism that can handle exceptions across different platforms. This might involve using platform-specific UI elements like `UIAlertView` for iOS or `Toast` for Android[2][5].

Customizing Newtonsoft.Json for Error Handling in MvvmCross

If you are using `Newtonsoft.Json` (which is common in MvvmCross), you can customize error handling by overriding the default JSON converter. Here’s an example:

csharp
public class MyJsonConverter : IMvxJsonConverter
{
    private static readonly JsonSerializerSettings Settings;

    static MyJsonConverter()
    {
        Settings = new JsonSerializerSettings
        {
            ReferenceLoopHandling = Newtonsoft.Json.ReferenceLoopHandling.Serialize,
            Converters = new List
            {
                new MvxEnumJsonConverter(),
            },
            DateFormatHandling = DateFormatHandling.IsoDateFormat,
            PreserveReferencesHandling = PreserveReferencesHandling.Objects
        };
    }

    public T DeserializeObject(string inputText)
    {
        try
        {
            return JsonConvert.DeserializeObject(inputText, Settings);
        }
        catch (JsonException ex)
        {
            // Handle the exception here
            return default(T);
        }
    }

    public string SerializeObject(object toSerialise)
    {
        try
        {
            return JsonConvert.SerializeObject(toSerialise, Formatting.None, Settings);
        }
        catch (JsonException ex)
        {
            // Handle the exception here
            return string.Empty;
        }
    }

    public object DeserializeObject(Type type, string inputText)
    {
        try
        {
            return JsonConvert.DeserializeObject(inputText, type, Settings);
        }
        catch (JsonException ex)
        {
            // Handle the exception here
            return null;
        }
    }
}

Then, register this custom converter in your `App.cs`:

csharp
Mvx.RegisterType();

Conclusion

While `JsonSerializerOptions` itself does not directly handle errors, you can use it to configure serialization settings that might prevent certain errors. For robust error handling in MvvmCross, consider using a combination of custom JSON converters and platform-specific error reporting mechanisms.