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using System.Collections;
using System.Collections.Generic;
using System.ComponentModel;
using System.Linq;
using System.Data.Linq.Mapping;
using System.Reflection;
using System.Runtime.CompilerServices;
namespace System.Data.Linq.Provider {
internal static class BindingList {
[MethodImpl(MethodImplOptions.NoInlining | MethodImplOptions.NoOptimization)]
internal static IBindingList Create<T>(DataContext context, IEnumerable<T> sequence) {
List<T> list = sequence.ToList();
MetaTable metaTable = context.Services.Model.GetTable(typeof(T));
if (metaTable != null) {
ITable table = context.GetTable(metaTable.RowType.Type);
Type bindingType = typeof(DataBindingList<>).MakeGenericType(metaTable.RowType.Type);
return (IBindingList)Activator.CreateInstance(bindingType,
BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic, null,
new object[] { list, table }, null
);
} else {
return new SortableBindingList<T>(list);
}
}
}
internal class DataBindingList<TEntity> : SortableBindingList<TEntity>
where TEntity : class {
private Table<TEntity> data;
private TEntity addNewInstance;
private TEntity cancelNewInstance;
private bool addingNewInstance;
internal DataBindingList(IList<TEntity> sequence, Table<TEntity> data)
: base(sequence != null ? sequence : new List<TEntity>()) {
if (sequence == null) {
throw Error.ArgumentNull("sequence");
}
if (data == null) {
throw Error.ArgumentNull("data");
}
this.data = data;
}
protected override object AddNewCore() {
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.InsertOnSubmit(item);
}
}
protected override void RemoveItem(int index) {
if (index >= 0 && index < Count && this[index] == cancelNewInstance) {
cancelNewInstance = null;
}
else {
this.data.DeleteOnSubmit(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.DeleteOnSubmit(removedItem);
}
this.data.InsertOnSubmit(item);
}
}
protected override void ClearItems() {
this.data.DeleteAllOnSubmit(this.data.ToList());
base.ClearItems();
}
public override void EndNew(int itemIndex) {
if (itemIndex >= 0 && itemIndex < Count && this[itemIndex] == addNewInstance) {
this.data.InsertOnSubmit(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);
}
}
}
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