Implement MultiSelectionComboBox

Author: timunie

src/MahApps.Metro/Controls/Helper/BindingHelper.cs

@@ -0,0 +1,93 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using System.Windows;
+using System.Windows.Data;
+
+namespace MahApps.Metro.Controls.Helper
+{
+    /// <summary>
+    /// A helper class to evaluate Bindings in code behind
+    /// </summary>
+    public static class BindingHelper
+    {
+        /// <summary>
+        /// A dummy property to initialize the binding to evaluate
+        /// </summary>
+        private static readonly DependencyProperty DummyProperty = DependencyProperty.RegisterAttached(
+            "Dummy",
+            typeof(object),
+            typeof(BindingHelper),
+            new UIPropertyMetadata(null));
+
+
+        /// <summary>
+        /// Evaluates a defined <see cref="Binding"/>-path on the given object
+        /// </summary>
+        /// <param name="source">the object to evaluate</param>
+        /// <param name="expression">the binding expression to evaluate</param>
+        /// <returns>the result of the <see cref="Binding"/></returns>
+        public static object Eval(object source, string expression)
+        {
+            Binding binding = new Binding(expression) { Source = source };
+            return Eval(binding);
+        }
+
+        /// <summary>
+        /// Evaluates a defined <see cref="Binding"/>-path on the given object
+        /// </summary>
+        /// <param name="source">the object to evaluate</param>
+        /// <param name="expression">the binding expression to evaluate</param>
+        /// <param name="format">the stringformat to use</param>
+        /// <returns>the result of the <see cref="Binding"/></returns>
+        public static object Eval(object source, string expression, string format)
+        {
+            Binding binding = new Binding(expression) { Source = source, StringFormat = format };
+            return Eval(binding);
+        }
+
+        /// <summary>
+        /// Evaluates a defined <see cref="Binding"/> on the given object
+        /// </summary>
+        /// <param name="binding">The <see cref="Binding"/> to evaluate</param>
+        /// <param name="source">the object to evaluate</param>
+        /// <returns></returns>
+        public static object Eval(Binding binding, object source)
+        {
+            if (binding is null) throw new ArgumentNullException(nameof(binding));
+
+            Binding newBinding = new Binding()
+            {
+                Source = source,
+                AsyncState = binding.AsyncState,
+                BindingGroupName = binding.BindingGroupName,
+                BindsDirectlyToSource = binding.BindsDirectlyToSource,
+                Path = binding.Path,
+                Converter = binding.Converter,
+                ConverterCulture = binding.ConverterCulture,
+                ConverterParameter = binding.ConverterParameter,
+                FallbackValue = binding.FallbackValue,
+                IsAsync = binding.IsAsync,
+                Mode = BindingMode.OneWay,
+                StringFormat = binding.StringFormat,
+                TargetNullValue = binding.TargetNullValue
+            };
+            return Eval(newBinding);
+        }
+
+        /// <summary>
+        /// Evaluates a defined <see cref="Binding"/> on the given <see cref="DependencyObject"/>
+        /// </summary>
+        /// <param name="binding">The <see cref="Binding"/> to evaluate</param>
+        /// <param name="dependencyObject">optional: The <see cref="DependencyObject"/> to evalutate</param>
+        /// <returns></returns>
+        public static object Eval(Binding binding, DependencyObject dependencyObject = null)
+        {
+            dependencyObject ??= new DependencyObject();
+            BindingOperations.SetBinding(dependencyObject, DummyProperty, binding);
+            return dependencyObject.GetValue(DummyProperty);
+        }
+    }
+}