Is required, [Required], and [JsonRequired] equivalent in Text.Json?

[ptr727]

I'm converting code from newtonsoft.json to text.json, and I'd like to get clarity on "required" attributes/fields?

Is C#11 required modifier the same as data annotations [Required]?
Does .NET8 Text.Json need [JsonRequired] if [Required] is already set?

[DaZombieKiller]

JsonRequiredAttribute should be equivalent to required (but the latter should probably be preferred when possible). When you mark something with required, at the IL level it gets marked with System.Runtime.CompilerServices.RequiredMemberAttribute. You can see where System.Text.Json determines if a member is required here. It first checks for JsonRequiredAttribute, and if that is not present it checks for RequiredMemberAttribute. System.ComponentModel.DataAnnotations.RequiredAttribute is unrelated and does not appear to be acknowledged by System.Text.Json.

[ptr727]

Thank you. If DataAnnotations are considered "unrelated", is there an equivalent in C#11 or Text.Json for [Obsolete]?
To be specific, I want the attribute to be read, e.g. old schema config, but not written, i.e. current config.

I am currently doing it using:

    private static void ExcludeObsoletePropertiesModifier(JsonTypeInfo typeInfo)
    {
        // Only process objects
        if (typeInfo.Kind != JsonTypeInfoKind.Object)
            return;

        // Iterate over all properties
        foreach (var property in typeInfo.Properties)
        {
            // Do not serialize [Obsolete] items
            if (property.AttributeProvider?.IsDefined(typeof(ObsoleteAttribute), true) == true)
                property.ShouldSerialize = (_, _) => false;
        }
    }