NumericUpDown: constrained the Value between the Min and Max values.

ExtendedWPFToolkitSolution/Src/WPFToolkit.Extended/Core/Primitives/InputBase.cs

@@ -57,7 +57,7 @@ namespace Microsoft.Windows.Controls.Primitives
 
         #region Value
 
-        public static readonly DependencyProperty ValueProperty = DependencyProperty.Register("Value", typeof(object), typeof(InputBase), new FrameworkPropertyMetadata(default(object), FrameworkPropertyMetadataOptions.BindsTwoWayByDefault, OnValuePropertyChanged));
+        public static readonly DependencyProperty ValueProperty = DependencyProperty.Register("Value", typeof(object), typeof(InputBase), new FrameworkPropertyMetadata(default(object), FrameworkPropertyMetadataOptions.BindsTwoWayByDefault, OnValuePropertyChanged, OnCoerceValuePropertyCallback));
         public virtual object Value
         {
             get { return (object)GetValue(ValueProperty); }
@@ -83,6 +83,20 @@ namespace Microsoft.Windows.Controls.Primitives
                         
         }
 
+        private static object OnCoerceValuePropertyCallback(DependencyObject d, object baseValue)
+        {
+            InputBase inputBase = d as InputBase;
+            if (inputBase != null)
+                return inputBase.OnCoerceValue(baseValue);
+            else
+                return baseValue;
+        }
+
+        protected virtual object OnCoerceValue(object value)
+        {
+            return value;
+        }
+
         #endregion //Value
 
         #region ValueType

ExtendedWPFToolkitSolution/Src/WPFToolkit.Extended/NumericUpDown/NumericUpDown.cs

@@ -101,6 +101,26 @@ namespace Microsoft.Windows.Controls
             SetValidSpinDirection();
         }
 
+        protected override object OnCoerceValue(object value)
+        {
+            if (value == null) return value;
+
+            double val = Convert.ToDouble(value);
+
+            if (val < Minimum)
+            {
+                return Minimum;
+            }
+            else if (val > Maximum)
+            {
+                return Maximum;
+            }
+            else
+            {
+                return value;
+            }
+        }
+
         protected override object ConvertTextToValue(string text)
         {
             object result = null;