TreeView 派生类: TreeViewEx 实现 NodeShowToolTip、NodeDo
2024-07-21 02:22:00
供稿：网友
// [email protected] invent
//一个 treeview 的派生类: treeviewex 实现 nodeshowtooltip、nodedoubleclick 事件
//1.实现了 nodeshowtooltip 事件,结合键盘 ctrl 键显示及设置 tooltiptext
//2.实现了 nodedoubleclick 事件,可在调用中只响应"叶子"节点
//3.点击 treeview 空白处不选中任何节点
//class1.cs
using system;
public class treeviewex : system.windows.forms.treeview
{
public event treeviewexeventhandler nodedoubleclick;
public event treeviewexeventhandler nodeshowtooltip;
private void onnodedoubleclick(system.windows.forms.treenode xx)
{
if(this.nodedoubleclick != null)
{
this.nodedoubleclick(this,new treeviewexeventargs(xx));
}
}
private void onnodeshowtooltip(system.windows.forms.treenode xx, system.windows.forms.tooltip yy)
{
if(this.nodeshowtooltip != null)
{
if ((xx != null) && (this.tooltip !=null))
this.nodeshowtooltip(this,new treeviewexeventargs(xx,this.tooltip));
}
}
protected override void ondoubleclick(system.eventargs e)
{
if (this.selectednode != null)
this.onnodedoubleclick(this.selectednode);
base.ondoubleclick(e);
}
private system.windows.forms.tooltip tooltip;
public treeviewex()
{
tooltip = new system.windows.forms.tooltip();
this.tooltip.initialdelay = 300;
this.tooltip.reshowdelay = 0;
}
protected override void onclick (system.eventargs e)
{
if (this.getnodeat(system.windows.forms.treeview.mouseposition.x,system.windows.forms.treeview.mouseposition.y) == null)
this.selectednode = null;
base.onclick(e);
}
protected override void onmousedown (system.windows.forms.mouseeventargs e)
{
if (this.getnodeat(e.x,e.y) == null)
this.selectednode = null;
base.onmousedown(e);
}
private system.windows.forms.treenode lasttreenode;
protected override void onmousemove (system.windows.forms.mouseeventargs e)
{
this.cursor = system.windows.forms.cursors.default ;
system.windows.forms.treenode treenode;
treenode = this.getnodeat(e.x,e.y) ;
if(treenode != null)
{
if( (system.windows.forms.control.modifierkeys & system.windows.forms.keys.control) != 0)
{
this.cursor = system.windows.forms.cursors.hand ;
if(treenode != lasttreenode | lasttreenode ==null )
{
lasttreenode = treenode;
this.tooltip.active = false;
this.onnodeshowtooltip(treenode,this.tooltip);
this.tooltip.active = true;
}
}
else
{
this.cursor = system.windows.forms.cursors.default ;
this.tooltip.active = false;
}
}
else
{
this.cursor = system.windows.forms.cursors.default ;
this.tooltip.active = false;
}
base.onmousemove(e);
}
}
public delegate void treeviewexeventhandler(object sender,treeviewexeventargs e);
public class treeviewexeventargs : system.eventargs
{
public treeviewexeventargs(system.windows.forms.treenode selectednode)
{
this.m_selectednode = selectednode;
}
public treeviewexeventargs(system.windows.forms.treenode node,system.windows.forms.tooltip nodetooltip)
{
this.m_nodetooltip = nodetooltip;
this.m_node = node;
}
public treeviewexeventargs(system.windows.forms.treenode node,string tooltiptext)
{
this.m_tooltiptext = tooltiptext;
}
private string m_tooltiptext;
private system.windows.forms.tooltip m_nodetooltip;
private system.windows.forms.treenode m_selectednode;
private system.windows.forms.treenode m_node;
public system.windows.forms.treenode selectednode
{
get
{
return this.m_selectednode;
}
}
public string tooltiptext
{
get
{
return this.tooltiptext;
}
set{m_tooltiptext = value;}
}
public system.windows.forms.treenode node
{
get
{
return this.m_node;
}
}
public system.windows.forms.tooltip nodetooltip
{
get
{
return this.m_nodetooltip;
}
}
}
public class treenodeex : system.windows.forms.treenode
{
public int getlevel()
{
int i = 0;
system.windows.forms.treenode xx =this.parent;
while ((xx = xx.parent) != null) i++;
return i;
}
}
//=================================================================
//调用示例
private treeviewex treeviewex1;
private void form1_load(object sender, system.eventargs e)
{
treeviewex1 = new treeviewex();
this.controls.add(treeviewex1);
treeviewex1.hideselection=false;
treeviewex1.nodedoubleclick +=new treeviewexeventhandler(treeviewex1_nodedoubleclick);
treeviewex1.nodeshowtooltip += new treeviewexeventhandler(this.treeviewex1_nodeshowtooltip);
treeviewex1.nodes.addrange(new system.windows.forms.treenode[]{
new system.windows.forms.treenode("root",
new system.windows.forms.treenode[]
{new system.windows.forms.treenode("a"),new system.windows.forms.treenode("b")}
),
new system.windows.forms.treenode("root1",
new system.windows.forms.treenode[]
{new system.windows.forms.treenode("a1"),new system.windows.forms.treenode("b1")}
)
}
);
}
public void treeviewex1_nodeshowtooltip (object sender,treeviewexeventargs e)
{
e.nodetooltip.settooltip (this.treeviewex1,"[" + e.node.text + "]{" );
}
private void treeviewex1_nodedoubleclick(object sender, treeviewexeventargs e)
{
if (e.selectednode.getnodecount(true)==0 )
system.windows.forms.messagebox.show(e.selectednode.text);
}
