Logger.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows.Controls;

namespace DataScraperGUI.Infrastructure {
    class Logger {
        private TextBox logBox = null;

        public Logger (TextBox lBox) {
            logBox = lBox;
        }

        private void Log (string message, string severity) {
            var sb = new StringBuilder();

            sb.Append("[");
            sb.Append(DateTime.Now.ToLocalTime());
            sb.Append("] ");
            sb.Append(severity);
            sb.Append(": ");
            sb.Append(message);
            sb.AppendLine();
            sb.Append(logBox.Text);

            logBox.Text = sb.ToString();
        }

        public void LogMessage (string message) {
            Log(message, "MESSAGE");
        }

        public void LogWarning (string message) {
            Log(message, "WARNING");
        }

        public void LogError (string message) {
            Log(message, "ERROR");
        }
    }
}