Debug log helper for Unity

FancyDebugLogger.cs

using UnityEngine;
using System;
using System.Linq.Expressions;
using System.Text;
using System.Globalization;
using System.Collections.Generic;

namespace Packet39
{
    public static class FancyDebugLogger
    {
        static string GetName<T>(Expression<Func<T>> expr)
        {
            if (expr == null) return "null";
            Expression body = expr.Body;

            if (body is UnaryExpression ue && ue.Operand != null)
                body = ue.Operand;

            if (body is MemberExpression me)
                return me.Member.Name;

            if (body is MethodCallExpression mce)
                return mce.Method.Name;

            return expr.Body.ToString();
        }

        static object GetValue<T>(Expression<Func<T>> expr)
        {
            if (expr == null) return null;
            try
            {
                return expr.Compile().Invoke();
            }
            catch
            {
                return null;
            }
        }

        static string FormatValue(object val)
        {
            if (val == null) return "null";
            if (val is float f) return f.ToString("G9", CultureInfo.InvariantCulture);
            if (val is double d) return d.ToString("G17", CultureInfo.InvariantCulture);
            if (val is IFormattable fmt) return fmt.ToString(null, CultureInfo.InvariantCulture);
            return val.ToString();
        }

        static void BuildAndLog(MonoBehaviour mb, string prefix, params KeyValuePair<string, object>[] items)
        {
            if (mb == null) return;

            // Unity rich text colors
            string className = $"<color=green>{mb.GetType().Name}</color>";
            string objectName = $"<color=yellow>{(mb.gameObject != null ? mb.gameObject.name : "null")}</color>";

            var sb = new StringBuilder();
            sb.Append('[').Append(className).Append("][")
                .Append(objectName).Append("] ");

            if (!string.IsNullOrEmpty(prefix))
            {
                sb.Append($"<color=#EE9B9B><b>{prefix}:</b></color> ");
            }

            for (int i = 0; i < items.Length; i++)
            {
                var kv = items[i];
                string varName = $"<color=white>{kv.Key}</color>";
                string varValue = $"<color=#00BFFF>{FormatValue(kv.Value)}</color>";
                sb.Append(varName).Append('=').Append(varValue);
                if (i < items.Length - 1) sb.Append(' ');
            }

            Debug.Log(sb.ToString());
        }
        
        public static void FancyLog(this MonoBehaviour mb, string prefix, params Expression<Func<object>>[] expressions)
        {
            var items = new List<KeyValuePair<string, object>>();
            foreach (var expr in expressions)
            {
                items.Add(new KeyValuePair<string, object>(GetName(expr), GetValue(expr)));
            }

            BuildAndLog(mb, prefix, items.ToArray());
        }

        public static void FancyLog(this MonoBehaviour mb, params Expression<Func<object>>[] expressions)
        {
            var items = new List<KeyValuePair<string, object>>();
            foreach (var expr in expressions)
            {
                items.Add(new KeyValuePair<string, object>(GetName(expr), GetValue(expr)));
            }

            BuildAndLog(mb, null, items.ToArray());
        }
    }
}

Usage:

this.FancyLog("Check this out",() => foundLetters, () => totalLetters, () => progess);

Will result in this console output:

[ProgressHelper][Progress] Check this out: foundLetters=2 totalLetters=65 progess=0.0307692308

Format:

[ClassName][GameObjectName] HeaderString (optional): VarName=Value VarName=Value ...

Output is colorized: