.NET by Patrik

Serialization

Serialization is the process of converting the state of an object into a form that can be persisted or transported. The complement of serialization is deserialization, which converts a stream into an object. Together, these processes allow data to be stored and transferred.

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When working with JsonElement in C#, calling methods like TryGetProperty on a default or uninitialized JsonElement can cause runtime exceptions. This usually happens when the JsonElement has not been properly assigned a value.

To avoid this issue, always check whether the JsonElement is valid before accessing its properties. A safe way to do this is by checking its ValueKind.

Here’s a safer extension method that returns a string property only if it exists and the element is valid:

public static string? GetStringProperty(this JsonElement element, string propertyName)
{
    if (element.ValueKind == JsonValueKind.Undefined)
        return null;

    return element.TryGetProperty(propertyName, out var prop) && prop.ValueKind == JsonValueKind.String
        ? prop.GetString()
        : null;
}

This ensures that your code won’t throw an InvalidOperationException when the JsonElement is default.

Use this method when reading from JSON documents where property existence isn’t guaranteed.

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