1 files changed, 73 insertions, 0 deletions
diff --git a/tools/Sandcastle/Source/BuildAssembler/BuildComponents/SwitchComponent.cs b/tools/Sandcastle/Source/BuildAssembler/BuildComponents/SwitchComponent.cs
new file mode 100644
index 0000000..47b1d6c
--- /dev/null
+++ b/tools/Sandcastle/Source/BuildAssembler/BuildComponents/SwitchComponent.cs
@@ -0,0 +1,73 @@
+// Copyright (c) Microsoft Corporation.  All rights reserved.
+//
+using System;
+using System.Collections.Generic;
+using System.Configuration;
+using System.Diagnostics;
+using System.Xml;
+using System.Xml.XPath;
+
+namespace Microsoft.Ddue.Tools {
+
+	public class SwitchComponent : BuildComponent {
+
+		public SwitchComponent(BuildAssembler assembler, XPathNavigator configuration) : base(assembler, configuration) {
+
+			// get the condition
+			XPathNavigator condition_element = configuration.SelectSingleNode("switch");
+			if (condition_element == null) {
+				throw new ConfigurationErrorsException("You must specifiy a condition using the <switch> statement with a 'value' attribute.");
+			}
+			string condition_value = condition_element.GetAttribute("value", String.Empty);
+			if (String.IsNullOrEmpty(condition_value)) {
+				throw new ConfigurationErrorsException("The switch statement must have a 'value' attribute, which is an xpath expression.");
+			}
+			condition = XPathExpression.Compile(condition_value);
+
+			// load the component stacks for each case
+			XPathNodeIterator case_elements = configuration.Select("case");
+			foreach (XPathNavigator case_element in case_elements) {
+				string case_value = case_element.GetAttribute("value", String.Empty);
+				BuildComponent[] components = BuildAssembler.LoadComponents(case_element);
+				cases.Add(case_value, components);
+			}
+		}
+
+		// data held by the component
+
+		private XPathExpression condition;
+
+		private Dictionary<string,IEnumerable<BuildComponent>> cases = new Dictionary<string,IEnumerable<BuildComponent>>();
+
+		// the action of the component
+
+		public override void Apply(XmlDocument document, string key) {
+
+			// evaluate the condition
+			string result = document.CreateNavigator().Evaluate(condition).ToString();
+
+			// get the corresponding component stack
+			IEnumerable<BuildComponent> components;
+			if (cases.TryGetValue(result, out components)) {
+				// apply it
+				foreach (BuildComponent component in components) {
+					component.Apply(document, key);
+				}
+			} else {
+				// no such case exists
+			}
+
+		}
+
+        public override void Dispose () {
+            foreach (IEnumerable<BuildComponent> components in cases.Values) {
+                foreach (BuildComponent component in components) {
+                    component.Dispose();
+                }
+            }
+            base.Dispose();
+        }
+
+	}
+
+}
+\ No newline at end of file