Question

如何C#中实现在TreeView查找某一节点

Answer 1

在TreeView查找某一节点，通常有两种方法，一种是递归的，一种不是递归，但都是深度优先算法。其中，非递归方法效率高些，而递归算法要简洁一些。
第一种，递归算法，代码如下：
private TreeNode FindNode( TreeNode tnParent, string strValue )
{
if( tnParent == null ) return null;
if( tnParent.Text == strValue ) return tnParent;
TreeNode tnRet = null;
foreach( TreeNode tn in tnParent.Nodes )
{
tnRet = FindNode( tn, strValue );
if( tnRet != null ) break;
}
return tnRet;
}
第二种，非递归算法，代码如下：
private TreeNode FindNode( TreeNode tnParent, string strValue )
{
if( tnParent == null ) return null;
if( tnParent.Text == strValue ) return tnParent;
else if( tnParent.Nodes.Count == 0 ) return null;
TreeNode tnCurrent, tnCurrentPar;
//Init node
tnCurrentPar = tnParent;
tnCurrent = tnCurrentPar.FirstNode;
while( tnCurrent != null && tnCurrent != tnParent )
{
while( tnCurrent != null )
{
if( tnCurrent.Text == strValue ) return tnCurrent;
else if( tnCurrent.Nodes.Count > 0 )
{
//Go into the deepest node in current sub-path
tnCurrentPar = tnCurrent;
tnCurrent = tnCurrent.FirstNode;
}
else if( tnCurrent != tnCurrentPar.LastNode )
{
//Goto next sible node
tnCurrent = tnCurrent.NextNode;
}
else
break;
}

//Go back to parent node till its has next sible node
while( tnCurrent != tnParent && tnCurrent == tnCurrentPar.LastNode )
{
tnCurrent = tnCurrentPar;
tnCurrentPar = tnCurrentPar.Parent;
}
//Goto next sible node
if( tnCurrent != tnParent )
tnCurrent = tnCurrent.NextNode;
}
return null;
}
程序调用，如下：
TreeNode tnRet = null;
foreach( TreeNode tn in yourTreeView.Nodes )
{
tnRet = FindNode( tn, yourValue );
if( tnRet != null ) break;
}