TweetDuck/Controls/NumericUpDownEx.cs

using System.ComponentModel;
using System.Windows.Forms;

namespace TweetDuck.Controls {
	sealed class NumericUpDownEx : NumericUpDown {
		public string TextSuffix { get; set ; }

		protected override void UpdateEditText() {
			base.UpdateEditText();

			if (LicenseManager.UsageMode != LicenseUsageMode.Designtime) {
				ChangingText = true;
				Text += TextSuffix;
				ChangingText = false;
			}
		}
	}
}