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namespace System.Web.UI.WebControls {
using System;
using System.Collections;
using System.Collections.Generic;
using System.ComponentModel;
using System.Globalization;
using System.Text;
using System.Web.UI;
public sealed class TreeNodeCollection : ICollection, IStateManager {
private List<TreeNode> _list;
private TreeNode _owner;
private bool _updateParent;
private int _version;
private bool _isTrackingViewState;
private List<LogItem> _log;
public TreeNodeCollection() : this(null, true) {
}
public TreeNodeCollection(TreeNode owner) : this(owner, true) {
}
internal TreeNodeCollection(TreeNode owner, bool updateParent) {
_owner = owner;
_list = new List<TreeNode>();
_updateParent = updateParent;
}
public int Count {
get {
return _list.Count;
}
}
public bool IsSynchronized {
get {
return ((ICollection)_list).IsSynchronized;
}
}
private List<LogItem> Log {
get {
if (_log == null) {
_log = new List<LogItem>();
}
return _log;
}
}
public object SyncRoot {
get {
return ((ICollection)_list).SyncRoot;
}
}
public TreeNode this[int index] {
get {
return _list[index];
}
}
public void Add(TreeNode child) {
AddAt(Count, child);
}
public void AddAt(int index, TreeNode child) {
if (child == null) {
throw new ArgumentNullException("child");
}
if (_updateParent) {
if (child.Owner != null && child.Parent == null) {
child.Owner.Nodes.Remove(child);
}
if (child.Parent != null) {
child.Parent.ChildNodes.Remove(child);
}
if (_owner != null) {
child.SetParent(_owner);
child.SetOwner(_owner.Owner);
}
}
_list.Insert(index, child);
_version++;
if (_isTrackingViewState) {
((IStateManager)child).TrackViewState();
child.SetDirty();
}
Log.Add(new LogItem(LogItemType.Insert, index, _isTrackingViewState));
}
public void Clear() {
if (this.Count == 0) return;
if (_owner != null) {
TreeView owner = _owner.Owner;
if (owner != null) {
// Clear checked nodes if necessary
if (owner.CheckedNodes.Count != 0) {
owner.CheckedNodes.Clear();
}
TreeNode current = owner.SelectedNode;
// Check if the selected item is under this collection
while (current != null) {
if (this.Contains(current)) {
owner.SetSelectedNode(null);
break;
}
current = current.Parent;
}
}
}
foreach (TreeNode node in _list) {
node.SetParent(null);
}
_list.Clear();
_version++;
if (_isTrackingViewState) {
// Clearing invalidates all previous log entries, so we can just clear them out and save some space
Log.Clear();
}
Log.Add(new LogItem(LogItemType.Clear, 0, _isTrackingViewState));
}
public void CopyTo(TreeNode[] nodeArray, int index) {
((ICollection)this).CopyTo(nodeArray, index);
}
public bool Contains(TreeNode c) {
return _list.Contains(c);
}
internal TreeNode FindNode(string[] path, int pos) {
if (pos == path.Length) {
return _owner;
}
string pathPart = TreeView.UnEscape(path[pos]);
for (int i = 0; i < Count; i++) {
TreeNode node = this[i];
if (node.Value == pathPart) {
return node.ChildNodes.FindNode(path, pos + 1);
}
}
return null;
}
public IEnumerator GetEnumerator() {
return new TreeNodeCollectionEnumerator(this);
}
public int IndexOf(TreeNode value) {
return _list.IndexOf(value);
}
public void Remove(TreeNode value) {
if (value == null) {
throw new ArgumentNullException("value");
}
int index = _list.IndexOf(value);
if (index != -1) {
RemoveAt(index);
}
}
public void RemoveAt(int index) {
TreeNode node = _list[index];
if (_updateParent) {
TreeView owner = node.Owner;
if (owner != null) {
if (owner.CheckedNodes.Count != 0) {
// We have to scan the whole tree of subnodes to remove any checked nodes
// (and unselect the selected node if it is a descendant).
// That could badly hurt performance, except that removing a node is a pretty
// exceptional event.
UnCheckUnSelectRecursive(node);
}
else {
// otherwise, we can just climb the tree up from the selected node
// to see if it is a descendant of the removed node.
TreeNode current = owner.SelectedNode;
// Check if the selected item is under this collection
while (current != null) {
if (current == node) {
owner.SetSelectedNode(null);
break;
}
current = current.Parent;
}
}
}
node.SetParent(null);
}
_list.RemoveAt(index);
_version++;
Log.Add(new LogItem(LogItemType.Remove, index, _isTrackingViewState));
}
internal void SetDirty() {
foreach (LogItem item in Log) {
item.Tracked = true;
}
for (int i = 0; i < Count; i++) {
this[i].SetDirty();
}
}
private static void UnCheckUnSelectRecursive(TreeNode node) {
TreeNodeCollection checkedNodes = node.Owner.CheckedNodes;
if (node.Checked) {
checkedNodes.Remove(node);
}
TreeNode selectedNode = node.Owner.SelectedNode;
if (node == selectedNode) {
node.Owner.SetSelectedNode(null);
selectedNode = null;
}
// Only recurse if there could be some more work to do
if (selectedNode != null || checkedNodes.Count != 0) {
foreach (TreeNode child in node.ChildNodes) {
UnCheckUnSelectRecursive(child);
}
}
}
#region ICollection implementation
void ICollection.CopyTo(Array array, int index) {
if (!(array is TreeNode[])) {
throw new ArgumentException(SR.GetString(SR.TreeNodeCollection_InvalidArrayType), "array");
}
_list.CopyTo((TreeNode[])array, index);
}
#endregion
#region IStateManager implementation
/// <internalonly/>
bool IStateManager.IsTrackingViewState {
get {
return _isTrackingViewState;
}
}
/// <internalonly/>
void IStateManager.LoadViewState(object state) {
object[] nodeState = (object[])state;
if (nodeState != null) {
if (nodeState[0] != null) {
string logString = (string)nodeState[0];
// Process each log entry
string[] items = logString.Split(',');
for (int i = 0; i < items.Length; i++) {
string[] parts = items[i].Split(':');
LogItemType type = (LogItemType)Int32.Parse(parts[0], CultureInfo.InvariantCulture);
int index = Int32.Parse(parts[1], CultureInfo.InvariantCulture);
if (type == LogItemType.Insert) {
if (_owner != null && _owner.Owner != null) {
AddAt(index, _owner.Owner.CreateNode());
}
else {
AddAt(index, new TreeNode());
}
}
else if (type == LogItemType.Remove) {
RemoveAt(index);
}
else if (type == LogItemType.Clear) {
Clear();
}
}
}
for (int i = 0; i < nodeState.Length - 1; i++) {
if ((nodeState[i + 1] != null) && (this[i] != null)) {
((IStateManager)this[i]).LoadViewState(nodeState[i + 1]);
}
}
}
}
/// <internalonly/>
object IStateManager.SaveViewState() {
object[] nodes = new object[Count + 1];
bool hasViewState = false;
if ((_log != null) && (_log.Count > 0)) {
// Construct a string representation of the log, delimiting entries with commas
// and seperator command and index with a colon
StringBuilder builder = new StringBuilder();
int realLogCount = 0;
for (int i = 0; i < _log.Count; i++) {
LogItem item = _log[i];
if (item.Tracked) {
builder.Append((int)item.Type);
builder.Append(":");
builder.Append(item.Index);
if (i < (_log.Count - 1)) {
builder.Append(",");
}
realLogCount++;
}
}
if (realLogCount > 0) {
nodes[0] = builder.ToString();
hasViewState = true;
}
}
for (int i = 0; i < Count; i++) {
nodes[i + 1] = ((IStateManager)this[i]).SaveViewState();
if (nodes[i + 1] != null) {
hasViewState = true;
}
}
return (hasViewState ? nodes : null);
}
/// <internalonly/>
void IStateManager.TrackViewState() {
_isTrackingViewState = true;
for (int i = 0; i < Count; i++) {
((IStateManager)this[i]).TrackViewState();
}
}
#endregion
/// <devdoc>
/// Convenience class for storing and using log entries.
/// </devdoc>
private class LogItem {
private LogItemType _type;
private int _index;
private bool _tracked;
public LogItem(LogItemType type, int index, bool tracked) {
_type = type;
_index = index;
_tracked = tracked;
}
public int Index {
get {
return _index;
}
}
public bool Tracked {
get {
return _tracked;
}
set {
_tracked = value;
}
}
public LogItemType Type {
get {
return _type;
}
}
}
/// <devdoc>
/// Convenience enumeration for identifying log commands
/// </devdoc>
private enum LogItemType {
Insert = 0,
Remove = 1,
Clear = 2
}
// This is a copy of the ArrayListEnumeratorSimple in ArrayList.cs
private class TreeNodeCollectionEnumerator : IEnumerator {
private TreeNodeCollection list;
private int index;
private int version;
private TreeNode currentElement;
internal TreeNodeCollectionEnumerator(TreeNodeCollection list) {
this.list = list;
this.index = -1;
version = list._version;
}
public bool MoveNext() {
if (version != list._version)
throw new InvalidOperationException(SR.GetString(SR.ListEnumVersionMismatch));
if (index < (list.Count - 1)) {
index++;
currentElement = list[index];
return true;
}
else
index = list.Count;
return false;
}
object IEnumerator.Current {
get {
return Current;
}
}
public TreeNode Current {
get {
if (index == -1)
throw new InvalidOperationException(SR.GetString(SR.ListEnumCurrentOutOfRange));
if (index >= list.Count)
throw new InvalidOperationException(SR.GetString(SR.ListEnumCurrentOutOfRange));
return currentElement;
}
}
public void Reset() {
if (version != list._version)
throw new InvalidOperationException(SR.GetString(SR.ListEnumVersionMismatch));
currentElement = null;
index = -1;
}
}
}
}
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