diff --git a/CodeWalker.WinForms/TextBoxFix.cs b/CodeWalker.WinForms/TextBoxFix.cs
index a01eadd..2f86fd4 100644
--- a/CodeWalker.WinForms/TextBoxFix.cs
+++ b/CodeWalker.WinForms/TextBoxFix.cs
@@ -1,17 +1,15 @@
 using System;
 using System.Collections.Generic;
-using System.ComponentModel;
-using System.Data;
-using System.Drawing;
-using System.Linq;
-using System.Text;
-using System.Threading.Tasks;
 using System.Windows.Forms;
 
 namespace CodeWalker.WinForms
 {
     public partial class TextBoxFix : TextBox
     {
+        bool ignoreChange = true;
+        List<string> storageUndo;
+        List<string> storageRedo;
+
         public TextBoxFix()
         {
             InitializeComponent();
@@ -22,17 +20,75 @@ namespace CodeWalker.WinForms
             base.OnPaint(pe);
         }
 
+        protected override void OnCreateControl()
+        {
+            base.OnCreateControl();
+            storageRedo = new List<string>();
+            storageUndo = new List<string> { Text };
+            ignoreChange = false;
+        }
+
         protected override bool ProcessCmdKey(ref Message msg, Keys keyData)
         {
-            //Fix for Ctrl-A not working in multiline textboxes.
+            //Fix for Ctrl-A/Z/Y not working in multiline textboxes.
             const int WM_KEYDOWN = 0x100;
             var keyCode = (Keys)(msg.WParam.ToInt32() & Convert.ToInt32(Keys.KeyCode));
-            if ((msg.Msg == WM_KEYDOWN && keyCode == Keys.A) && (ModifierKeys == Keys.Control) && Focused)
+            if (msg.Msg == WM_KEYDOWN && (ModifierKeys == Keys.Control) && Focused)
             {
-                SelectAll();
-                return true;
+                if (keyCode == Keys.A)
+                {
+                    SelectAll();
+                    return true;
+                }
+                if (keyCode == Keys.Z)
+                {
+                    Undo();
+                    return true;
+                }
+                if (keyCode == Keys.Y)
+                {
+                    Redo();
+                    return true;
+                }
             }
             return base.ProcessCmdKey(ref msg, keyData);
         }
+        protected override void OnTextChanged(EventArgs e)
+        {
+            base.OnTextChanged(e);
+
+            if (!ignoreChange)
+            {
+                ClearUndo();
+                if (storageUndo.Count > 2048) storageUndo.RemoveAt(0);
+                if (storageRedo.Count > 2048) storageRedo.RemoveAt(0);
+
+                storageUndo.Add(Text);
+            }
+        }
+
+        public void Redo()
+        {
+            if (storageRedo.Count > 0)
+            {
+                ignoreChange = true;
+                Text = storageRedo[storageRedo.Count - 1];
+                storageUndo.Add(Text);
+                storageRedo.RemoveAt(storageRedo.Count - 1);
+                ignoreChange = false;
+            }
+        }
+
+        public new void Undo()
+        {
+            if (storageUndo.Count > 1)
+            {
+                ignoreChange = true;
+                Text = storageUndo[storageUndo.Count - 2];
+                storageRedo.Add(storageUndo[storageUndo.Count - 1]);
+                storageUndo.RemoveAt(storageUndo.Count - 1);
+                ignoreChange = false;
+            }
+        }
     }
 }