能不能把对象保存在ViewState中啊,如何序列号TreeView,ViewState在App_Code下面如何获取啊
public class TreeNodesExpandStateManager : IDisposable
{
TreeView _tree;
List<TreeNode> nodes = new List<TreeNode>();
public static string SessionKey = "TreeNodesExpandState";
public TreeNodesExpandStateManager(TreeView tree)
{
_tree = tree;
} /// <summary>
/// 保存当前树的展开状态
/// </summary>
public void SaveExpandState()
{
foreach (TreeNode node in this._tree.Nodes)
{
SearchExpandedNode(node);
}
} private void SearchExpandedNode(TreeNode node)
{
if (node == null)
return;
else
{
if (node.Expanded ?? false)
{
nodes.Add(node);
foreach (TreeNode item in node.ChildNodes)
{
SearchExpandedNode(item);
}
}
}
} /// <summary>
/// 恢复当前树的展开状态
/// </summary>
public void RestoreExpandState()
{
foreach (TreeNode node in this._tree.Nodes)
{
SetNodeExpandState(node);
}
} /// <summary>
/// 用于跨页操作时,恢复到指定树
/// </summary>
/// <param name="tree"></param>
public void RestoreExpandStateToTree(TreeView tree)
{
foreach (TreeNode node in tree.Nodes)
{
SetNodeExpandState(node);
}
} private void SetNodeExpandState(TreeNode node)
{
if (node == null)
return;
else
{
if (this.nodes.Contains(node, new EqualEntity()))
{
node.Expand();
foreach (TreeNode item in node.ChildNodes)
{
SetNodeExpandState(item);
}
}
}
} /// <summary>
/// 将指定树展开状态存入会话,一般在树的展开和合闭事件中调用
/// </summary>
/// <param name="tree">目标树</param>
public static void SaveExpandStateInSession(TreeView tree, string sessionKey)
{
if (tree == null)
return;
TreeNodesExpandStateManager manager = new TreeNodesExpandStateManager(tree);
manager.SaveExpandState();
HttpContext.Current.Session[sessionKey] = manager;
} /// <summary>
/// 将指定树展开状态存入默认会话,一般在树的展开和合闭事件中调用
/// </summary>
/// <param name="tree">目标树</param>
public static void SaveExpandStateInSession(TreeView tree)
{
SaveExpandStateInSession(tree, SessionKey);
} /// <summary>
/// 将Session中的结点展开状态恢复到指定树,在树结点添加结束后调用
/// </summary>
/// <param name="tree">目标树</param>
public static void RestoreExpandStateToTreeFromSession(TreeView tree, string sessionKey)
{
if (HttpContext.Current.Session[sessionKey] == null || tree == null)
return;
TreeNodesExpandStateManager manager = HttpContext.Current.Session[sessionKey] as TreeNodesExpandStateManager;
manager.RestoreExpandStateToTree(tree);
}
/// <summary>
/// 将默认Session中的结点展开状态恢复到指定树,在树结点添加结束后调用
/// </summary>
/// <param name="tree">目标树</param>
public static void RestoreExpandStateToTreeFromSession(TreeView tree)
{
RestoreExpandStateToTreeFromSession(tree, SessionKey);
} #region IDisposable 成员 public void Dispose()
{
this.nodes.Clear();
this.nodes = null;
this._tree.Dispose();
} #endregion ~TreeNodesExpandStateManager()
{
this.Dispose();
}
public class EqualEntity : IEqualityComparer<TreeNode>
{
#region IEqualityComparer<TreeNode> 成员 public bool Equals(TreeNode x, TreeNode y)
{
if (x == null || y == null)
return false;
return x.Value.Equals(y.Value);
} public int GetHashCode(TreeNode obj)
{
return obj.GetHashCode();
} #endregion
}
}
public class TreeNodesExpandStateManager : IDisposable
{
TreeView _tree;
List<TreeNode> nodes = new List<TreeNode>();
public static string SessionKey = "TreeNodesExpandState";
public TreeNodesExpandStateManager(TreeView tree)
{
_tree = tree;
} /// <summary>
/// 保存当前树的展开状态
/// </summary>
public void SaveExpandState()
{
foreach (TreeNode node in this._tree.Nodes)
{
SearchExpandedNode(node);
}
} private void SearchExpandedNode(TreeNode node)
{
if (node == null)
return;
else
{
if (node.Expanded ?? false)
{
nodes.Add(node);
foreach (TreeNode item in node.ChildNodes)
{
SearchExpandedNode(item);
}
}
}
} /// <summary>
/// 恢复当前树的展开状态
/// </summary>
public void RestoreExpandState()
{
foreach (TreeNode node in this._tree.Nodes)
{
SetNodeExpandState(node);
}
} /// <summary>
/// 用于跨页操作时,恢复到指定树
/// </summary>
/// <param name="tree"></param>
public void RestoreExpandStateToTree(TreeView tree)
{
foreach (TreeNode node in tree.Nodes)
{
SetNodeExpandState(node);
}
} private void SetNodeExpandState(TreeNode node)
{
if (node == null)
return;
else
{
if (this.nodes.Contains(node, new EqualEntity()))
{
node.Expand();
foreach (TreeNode item in node.ChildNodes)
{
SetNodeExpandState(item);
}
}
}
} /// <summary>
/// 将指定树展开状态存入会话,一般在树的展开和合闭事件中调用
/// </summary>
/// <param name="tree">目标树</param>
public static void SaveExpandStateInSession(TreeView tree, string sessionKey)
{
if (tree == null)
return;
TreeNodesExpandStateManager manager = new TreeNodesExpandStateManager(tree);
manager.SaveExpandState();
HttpContext.Current.Session[sessionKey] = manager;
} /// <summary>
/// 将指定树展开状态存入默认会话,一般在树的展开和合闭事件中调用
/// </summary>
/// <param name="tree">目标树</param>
public static void SaveExpandStateInSession(TreeView tree)
{
SaveExpandStateInSession(tree, SessionKey);
} /// <summary>
/// 将Session中的结点展开状态恢复到指定树,在树结点添加结束后调用
/// </summary>
/// <param name="tree">目标树</param>
public static void RestoreExpandStateToTreeFromSession(TreeView tree, string sessionKey)
{
if (HttpContext.Current.Session[sessionKey] == null || tree == null)
return;
TreeNodesExpandStateManager manager = HttpContext.Current.Session[sessionKey] as TreeNodesExpandStateManager;
manager.RestoreExpandStateToTree(tree);
}
/// <summary>
/// 将默认Session中的结点展开状态恢复到指定树,在树结点添加结束后调用
/// </summary>
/// <param name="tree">目标树</param>
public static void RestoreExpandStateToTreeFromSession(TreeView tree)
{
RestoreExpandStateToTreeFromSession(tree, SessionKey);
} #region IDisposable 成员 public void Dispose()
{
this.nodes.Clear();
this.nodes = null;
this._tree.Dispose();
} #endregion ~TreeNodesExpandStateManager()
{
this.Dispose();
}
public class EqualEntity : IEqualityComparer<TreeNode>
{
#region IEqualityComparer<TreeNode> 成员 public bool Equals(TreeNode x, TreeNode y)
{
if (x == null || y == null)
return false;
return x.Value.Equals(y.Value);
} public int GetHashCode(TreeNode obj)
{
return obj.GetHashCode();
} #endregion
}
}
比如当前索引啦, 小的数字, 之类的.可以限定的基本数据类型上, 不字符串长度要有限制.供回发时当作恢复现场把柄的.要是把现场整个都放到 viewstate , 无异于找死.
----------------------------------可以,序列化后保存.=======================================如何序列号TreeView,
-----------------------------------是想问如何序列化TreeView? 因为TreeView 本身没有 SerializableAttribute 标记需要你用辅助类来实现 TreeView 的 序列化=======================================ViewState在App_Code下面如何获取啊不知道你想问什么
what do you want to do ?