优化更新代码，添加界面功能并整合

WPFluent/Controls/NumberBox/NumberBoxValidationMode.cs

@@ -0,0 +1,24 @@
+
+
+
+// This Source Code is partially based on the source code provided by the .NET Foundation.
+
+// ReSharper disable once CheckNamespace
+namespace WPFluent.Controls;
+
+/// <summary>
+/// Defines values that specify the input validation behavior of a <see cref="NumberBox"/> when invalid input is
+/// entered.
+/// </summary>
+public enum NumberBoxValidationMode
+{
+    /// <summary>
+    /// Input validation is disabled.
+    /// </summary>
+    InvalidInputOverwritten,
+
+    /// <summary>
+    /// Invalid input is replaced by <see cref="NumberBox"/> PlaceholderText text.
+    /// </summary>
+    Disabled,
+}