Add project files.

AspNetCore.Extensions/Websockets/Converters/TextWebSocketMessageConverter.cs

@@ -0,0 +1,27 @@
+using System.Text;
+
+namespace AspNetCore.Extensions.Websockets.Converters;
+
+public sealed class TextWebSocketMessageConverter : WebSocketMessageConverter<TextContent>
+{
+    public override TextContent ConvertTo(WebSocketConverterRequest request)
+    {
+        if (request.Type is not System.Net.WebSockets.WebSocketMessageType.Text)
+        {
+            throw new InvalidOperationException($"Cannot parse message of type {request.Type}");
+        }
+
+        var message = Encoding.UTF8.GetString(request.Payload!);
+        return new TextContent { Text = message };
+    }
+
+    public override WebSocketConverterResponse ConvertFrom(TextContent message)
+    {
+        return new WebSocketConverterResponse
+        {
+            Type = System.Net.WebSockets.WebSocketMessageType.Text,
+            EndOfMessage = true,
+            Payload = Encoding.UTF8.GetBytes(message.Text ?? string.Empty)
+        };
+    }
+}