EnumString.md

EnumString

Namespace: SpawnDev.SpawnJS
Inheritance: EnumString (abstract) -> EnumString<T>
Source: SpawnDev.SpawnJS/EnumString.cs

EnumString<T> provides bidirectional conversion between C# enums and JavaScript string values. Many JavaScript APIs use string constants (e.g., "audio", "video", "arraybuffer") where C# would use an enum. EnumString maps between the two using [JsonPropertyName] attributes on enum members to define the JS string representation. It supports implicit conversions in both directions.

Properties

Property	Type	Description
String	string?	The JavaScript string value. Setting this updates Enum and IsDefined.
Enum	T?	The C# enum value. Setting this updates String and IsDefined.
IsDefined	bool	True if the current value maps to a known enum member.

Constructors

new EnumString<T>()               // Empty
new EnumString<T>(T value)        // From enum value
new EnumString<T>(string value)   // From string value

Implicit Conversions

// Enum -> EnumString<T>
EnumString<MediaType> es = MediaType.Audio;

// EnumString<T> -> Enum
MediaType mt = es;

// String -> EnumString<T>
EnumString<MediaType> es2 = "audio";

// EnumString<T> -> String
string s = es2;

// Nullable variants also supported
EnumString<MediaType>? nullable = (MediaType?)null;
MediaType? nullableEnum = (EnumString<MediaType>?)null;

Example - Defining an Enum for JS Strings

using System.Text.Json.Serialization;

public enum BinaryType
{
    [JsonPropertyName("blob")]
    Blob,
    [JsonPropertyName("arraybuffer")]
    ArrayBuffer
}

public enum ReadyState
{
    [JsonPropertyName("loading")]
    Loading,
    [JsonPropertyName("interactive")]
    Interactive,
    [JsonPropertyName("complete")]
    Complete
}

Example - Using in a Wrapper

public class WebSocket : EventTarget
{
    public WebSocket(SpawnJSObjectReference _ref) : base(_ref) { }

    // BinaryType is a string in JS: "blob" or "arraybuffer"
    public EnumString<BinaryType> BinaryType
    {
        get => JSRef!.Get<EnumString<BinaryType>>("binaryType");
        set => JSRef!.Set("binaryType", value);
    }
}

// Usage
using var ws = new WebSocket("wss://example.com");
ws.BinaryType = BinaryType.ArrayBuffer;  // Sets "arraybuffer" in JS

// Read back
BinaryType bt = ws.BinaryType;  // Implicit conversion to enum
string btStr = ws.BinaryType;   // Implicit conversion to string: "arraybuffer"

Example - Handling Unknown Values

EnumString<ReadyState> state = JS.Get<EnumString<ReadyState>>("document.readyState");

if (state.IsDefined)
{
    ReadyState rs = state; // safe to convert
    switch (rs)
    {
        case ReadyState.Complete:
            Console.WriteLine("Document is loaded");
            break;
    }
}
else
{
    Console.WriteLine($"Unknown readyState: {state.String}");
}

JSON Serialization

EnumString serializes to a plain JSON string using the [JsonPropertyName] value:

"arraybuffer"

If the EnumString is null, it serializes as JSON null.