.Net Core 3.0 JsonSerializer populate existing object

Question

I\'m preparing a migration from ASP.NET Core 2.2 to 3.0.

As I don\'t use more advanced JSON features (but maybe one as described below), and 3.0 now comes with a buil

Answer 1

If its just one usage and you don't want to add extra dependencies / lots of code, you don't mind a bit of inefficiency and I've not missed something obvious, you can just use:

    private static T ParseWithTemplate(T template, string input) 
    {
        var ignoreNulls = new JsonSerializerOptions() { IgnoreNullValues = true };
        var templateJson = JsonSerializer.ToString(template, ignoreNulls);
        var combinedData = templateJson.TrimEnd('}') + "," + input.TrimStart().TrimStart('{');
        return JsonSerializer.Parse(combinedData);
    }