Imported Upstream version 4.0.0~alpha1

Former-commit-id: 806294f5ded97629b74c85c09952f2a74fe182d9

external/referencesource/System.Data.Linq/EntitySetDataBindingList.cs

@@ -0,0 +1,108 @@
+using System.Collections.Generic;
+using System.ComponentModel;
+using System.Linq;
+using System.Reflection;
+using System.Diagnostics.CodeAnalysis;
+
+namespace System.Data.Linq {
+    internal class EntitySetBindingList<TEntity> : SortableBindingList<TEntity>
+        where TEntity : class {
+        private EntitySet<TEntity> data;
+        private TEntity addNewInstance;
+        private TEntity cancelNewInstance;
+        private bool addingNewInstance;
+
+        internal EntitySetBindingList(IList<TEntity> sequence, EntitySet<TEntity> data)
+            : base(sequence) {
+            if (sequence == null) {
+                throw Error.ArgumentNull("sequence");
+            }
+            if (data == null) {
+                throw Error.ArgumentNull("data");
+            }
+
+            this.data = data;
+        }
+
+        [SuppressMessage("Microsoft.Performance", "CA1822:MarkMembersAsStatic", Justification="Unknown reason.")]
+        private void ThrowEntitySetErrorsIfTypeInappropriate() {
+            Type type = typeof(TEntity);
+
+            if (type.IsAbstract) {
+                throw Error.EntitySetDataBindingWithAbstractBaseClass(type.Name);
+            }
+            if (type.GetConstructor(System.Type.EmptyTypes) == null) {
+                throw Error.EntitySetDataBindingWithNonPublicDefaultConstructor(type.Name);
+            }
+        }
+
+        protected override object AddNewCore() {
+            ThrowEntitySetErrorsIfTypeInappropriate();
+            addingNewInstance = true;
+            addNewInstance = (TEntity)base.AddNewCore();
+            return addNewInstance;
+        }
+  
+        protected override void InsertItem(int index, TEntity item) {
+            base.InsertItem(index, item);
+            if (!addingNewInstance && index >= 0 && index <= Count) {
+                this.data.Insert(index, item);
+            }
+        }
+
+        protected override void RemoveItem(int index) {
+            if (index >= 0 && index < Count && this[index] == cancelNewInstance) {
+                cancelNewInstance = null;
+            }
+            else {
+                this.data.Remove(this[index]);
+            }
+
+            base.RemoveItem(index);
+        }
+
+        protected override void SetItem(int index, TEntity item) {
+            TEntity removedItem = this[index];
+            base.SetItem(index, item);
+            if (index >= 0 && index < Count) {
+                //Check to see if the user is trying to set an item that is currently being added via AddNew
+                //If so then the list should not continue the AddNew; but instead add the item
+                //that is being passed in.
+                if (removedItem == addNewInstance) {
+                    addNewInstance = null;
+                    addingNewInstance = false;
+                }
+                else {
+                    this.data.Remove(removedItem);
+                }
+                this.data.Insert(index,item);
+            }
+
+        }
+
+        protected override void ClearItems() {
+            this.data.Clear();
+            base.ClearItems();
+        }
+
+        public override void EndNew(int itemIndex) {
+            if (itemIndex >= 0 && itemIndex < Count && this[itemIndex] == addNewInstance) {
+                this.data.Add(addNewInstance);
+                addNewInstance = null;
+                addingNewInstance = false;
+            }
+
+            base.EndNew(itemIndex);
+        }
+
+        public override void CancelNew(int itemIndex) {
+            if (itemIndex >= 0 && itemIndex < Count && this[itemIndex] == addNewInstance) {
+                cancelNewInstance = addNewInstance;
+                addNewInstance = null;
+                addingNewInstance = false;
+            }
+
+            base.CancelNew(itemIndex);
+        }
+    }
+}