support for .NET framework 3.5

Still have bugs

Net35/HandyControl_Net35/Tools/Helper/AnimationHelper.cs

@@ -0,0 +1,34 @@
+using System;
+using System.Windows;
+using System.Windows.Media.Animation;
+
+namespace HandyControl.Tools
+{
+    /// <summary>
+    ///     包含一些常用的动画辅助方法
+    /// </summary>
+    public class AnimationHelper
+    {
+        /// <summary>
+        ///     创建一个Thickness动画
+        /// </summary>
+        /// <param name="thickness"></param>
+        /// <param name="milliseconds"></param>
+        /// <returns></returns>
+        public static ThicknessAnimation CreateAnimation(Thickness thickness = default(Thickness), double milliseconds = 200)
+        {
+            return new ThicknessAnimation(thickness, new Duration(TimeSpan.FromMilliseconds(milliseconds)));
+        }
+
+        /// <summary>
+        ///     创建一个Double动画
+        /// </summary>
+        /// <param name="toValue"></param>
+        /// <param name="milliseconds"></param>
+        /// <returns></returns>
+        public static DoubleAnimation CreateAnimation(double toValue, double milliseconds = 200)
+        {
+            return new DoubleAnimation(toValue, new Duration(TimeSpan.FromMilliseconds(milliseconds)));
+        }
+    }
+}