三态CheckBox例子

首先三态节点树必须是带有CheckBox的树，这里简单说明一下所做的三态树。所谓三态是指：选中状态，半选中状态，未选中状态。选中状态：节点的CheckBox打勾；半选中状态：节点的CheckBox打勾，但为灰色；未选中状态：CheckBox不打勾。

       其次，子节点全选中，父节点选中；子节点全不选中，父节点不选中；子节点选中但未全部选中，父节点半选中；子节点半选中，父节点半选中；父节点选中子节点全选中，父节点取消，子节点全取消。

代码如下：客户端（JAVASCRIPT）

<script type="text/jscript" language="javascript">   
    
function ShowLegend(ControlID,LegendInfo)
{
    alert(LegendInfo);
    var para = "LegendInfo="+LegendInfo + "&Visible=" + document.all(ControlID).checked;
    var myAjax = new Ajax.Request('../ajax/WebFormChangeLegendVisible.aspx',{method: 'get', parameters:para, onComplete: RefreshMap});
}

function RefreshMap(request)
{
    var content = request.responseText;
    parent.mapview.document.forms[0].submit();
}

function OnTreeNodeChecked() 
{ 
    var element = window.event.srcElement; 
    if (!IsCheckBox(element)) 
        return; 
    
    var isChecked = element.checked; 
    var isIndeterminate = element.Indeterminate;
    var tree = TV2_GetTreeById("TreeView1"); 
    var node = TV2_GetNode(tree,element); 

    TV2_SetChildNodesCheckState(node,isChecked); 
    //alert(element.id);

    var parent = TV2_GetParentNode(tree,node); 
    TV2_NodeOnChildNodeCheckedChanged(tree,parent,isChecked); 
    
    //document.all("txtSelectID").value = "";
    var aCheckBox = document.getElementsByTagName("input");
    for (var i=0;i<aCheckBox.length;i++)
    {
        if(aCheckBox[i].type == "checkbox") 
        {
            if(aCheckBox[i].checked)
            {
                var sID = aCheckBox[i].id;
                sID = sID.substring(0,sID.indexOf("CheckBox")); 
                var obja = document.getElementById(sID.replace('n','t'));            
                var sSelectID = obja.href.replace("javascript:__doPostBack('TreeView1','s')","")
                sSelectID = sSelectID.replace("')","")
                var aSelectID = sSelectID.split("\")
            }
        }
    }

} 

//设置子节点CheckBox的状态
function TV2_SetChildNodesCheckState(node,isChecked) 
{ 
    var childNodes = TV2i_GetChildNodesDiv(node); 
    if(childNodes == null) 
        return; 

    var inputs = WebForm_GetElementsByTagName(childNodes,"INPUT"); 
    if(inputs == null || inputs.length == 0) 
        return; 

    for(var i = 0; i < inputs.length; i++) 
    { 
        if(IsCheckBox(inputs[i])) 
            inputs[i].checked = isChecked; 
            inputs[i].indeterminate = false; //父结点改变状态，子节点灰色消失
            
    } 
} 


//当子节点CheckBox状态改变引发的父结点状态改变
function TV2_NodeOnChildNodeCheckedChanged(tree,node,isChecked,isIndeterminate) 
{ 
    if(node == null) 
        return; 

    var childNodes = TV2_GetChildNodes(tree,node); 

    if(childNodes == null || childNodes.length == 0) 
        return; 

    var isAllSame = true; 
    var Nodegray = isIndeterminate;  //节点的灰色
    for(var i = 0; i < childNodes.length; i++)  //循环子节点
    { 
        var item = childNodes[i];               //获取一个子节点
        var value = TV2_NodeGetChecked(item);   //获取子节点的checked状态
        var value2 = TV2_NodeGetindeterminate(item);   //获取子节点的isIndeterminate状态
        if(isChecked != value)       //如果checkbox的选中状态不相同
        { 
            isAllSame = false; 
            Nodegray = true;
            break; 
        } 
        if(value2)
        {
            Nodegray = true;
        }
    } 

    var parent = TV2_GetParentNode(tree,node); 
    if(isAllSame)   //为真：即checkbox的选中状态相同
    { 
        TV2_NodeSetChecked(tree,node,isChecked,Nodegray);  //设置当前节点状态
        TV2_NodeOnChildNodeCheckedChanged(tree,parent,isChecked,Nodegray);   //向父结点递归
    } 
    else            //为假，即checkbox的选中状态不相同，或出于灰色状态
    { 
        TV2_NodeSetChecked(tree,node,true,Nodegray); //设置当前节点状态
        TV2_NodeOnChildNodeCheckedChanged(tree,parent,true,Nodegray);         //向父结点递归
    } 
} 


//get node relative element(etc. checkbox) 
function TV2_GetNode(tree,element) 
{ 
    var id = element.id.replace(tree.id,""); 
    id = id.toLowerCase().replace(element.type,""); 
    id = tree.id + id; 

    var node = document.getElementById(id); 
    if(node == null) //leaf node, no "A" node 
        return element; 
    return node; 
} 

//get parent node 
function TV2_GetParentNode(tree,node) 
{ 
    var div = WebForm_GetParentByTagName(node,"DIV"); 

    var table = div.previousSibling; 
    if(table == null) 
        return null; 

    return TV2i_GetNodeInElement(tree,table); 
} 

//get child nodes array 
function TV2_GetChildNodes(tree,node) 
{ 
    if(TV2_NodeIsLeaf(node)) 
        return null; 

    var children = new Array(); 
    var div = TV2i_GetChildNodesDiv(node); 
    var index = 0; 

    for(var i = 0; i < div.childNodes.length; i++) 
    { 
        var element = div.childNodes[i]; 
        if(element.tagName != "TABLE") 
        continue; 

        var child = TV2i_GetNodeInElement(tree,element); 
        if(child != null) 
            children[index++] = child; 
    } 
    return children; 
} 

function TV2_NodeIsLeaf(node) 
{ 
    return !(node.tagName == "A"); //Todo 
} 

//读取结点的Checked状态
function TV2_NodeGetChecked(node) 
{ 
    var checkbox = TV2i_NodeGetCheckBox(node); 
    return checkbox.checked; 
} 

//读取节点的indeterminate状态
function TV2_NodeGetindeterminate(node) 
{ 
    var checkbox = TV2i_NodeGetCheckBox(node); 
    return checkbox.Indeterminate; 
} 

//判断：只要该节点有一个子节点被选中，则该节点一定被选中，若有一个子节点为灰色，则该节点为灰色 
function TV2_NodeSetChecked(tree,node,isChecked,isIndeterminate) 
{ 
    var checkbox = TV2i_NodeGetCheckBox(node); 
    if(checkbox != null) 
    { 
        var childNodes = TV2_GetChildNodes(tree,node);  //获取子节点的集合
        for(var i = 0; i < childNodes.length; i++) 
        { 
            var item = childNodes[i];               //获取一个子节点
            var value = TV2_NodeGetChecked(item);   //子节点的选中状态
            var value2 = TV2_NodeGetindeterminate(item); //子节点的灰色状态
            if(value)     
            { 
                isChecked = true ;  
                break; 
            } 
            if(value2)//子节点为灰色
            {
            isInDeterminate=true;
            break;
            }
        } 
        checkbox.checked = isChecked;   //结点选中状态
        checkbox.indeterminate = isIndeterminate; //结点是否灰色
    } 
} 

function IsCheckBox(element) 
{ 
    if(element == null) 
        return false; 
    return (element.tagName == "INPUT" && element.type.toLowerCase() == "checkbox"); 
} 

//get tree 
function TV2_GetTreeById(id) 
{ 
    return document.getElementById(id); 
} 


//get div contains child nodes 
function TV2i_GetChildNodesDiv(node) 
{ 
    if(TV2_NodeIsLeaf(node)) 
        return null; 

    var childNodsDivId = node.id + "Nodes"; 
    return document.getElementById( childNodsDivId ); 
} 

    //find node in element 
function TV2i_GetNodeInElement(tree,element) 
{ 
    var node = TV2i_GetNodeInElementA(tree,element); 
    if(node == null) 
    { 
        node = TV2i_GetNodeInElementInput(tree,element); 
    } 
    return node; 
} 

//find "A" node 
function TV2i_GetNodeInElementA(tree,element) 
{ 
    var as = WebForm_GetElementsByTagName(element,"A"); 
    if(as== null || as.length == 0) 
        return null; 

    var regexp = new RegExp("^" + tree.id + "n\d+$"); 

    for(var i = 0; i < as.length; i++) 
    { 
        if(as[i].id.match(regexp)) 
        { 
            return as[i]; 
        } 
    } 
    return null; 
} 

//find "INPUT" node 
function TV2i_GetNodeInElementInput(tree,element) 
{ 
    var as = WebForm_GetElementsByTagName(element,"INPUT"); 
    if(as== null || as.length == 0) 
        return null; 

    var regexp = new RegExp("^" + tree.id + "n\d+"); 
    for(var i = 0; i < as.length; i++) 
    { 
        if(as[i].id.match(regexp)) 
        { 
            return as[i]; 
        } 
    } 
    return null; 
} 

//get checkbox of node 
function TV2i_NodeGetCheckBox(node) 
{ 
    if(IsCheckBox(node)) 
        return node; 

    var id = node.id + "CheckBox"; 
    return document.getElementById(id); 
}        

function showtab(m,n,count){
    var strPic1='url(../image/1.bmp)';
    var strPic2='url(../image/2.bmp)';
    if (m==8) {
    strPic1='url(../image/switch03_1.gif)';
    strPic2='url(../image/switch03_2.gif)';    }

    for(var i=1;i<=count;i++){
        if (i==n){            
            getObject(m+'_'+i).style.background=strPic1;
            getObject('tab_'+m+'_'+i).style.display='';            
            }
        else {
            getObject(m+'_'+i).style.background=strPic2;
            getObject('tab_'+m+'_'+i).style.display='none';
            }
    }
}
function getObject(objectId) {
    if(document.getElementById && document.getElementById(objectId)) {
    // W3C DOM
    return document.getElementById(objectId);
    } else if (document.all && document.all(objectId)) {
    // MSIE 4 DOM
    return document.all(objectId);
    } else if (document.layers && document.layers[objectId]) {
    // NN 4 DOM.. note: this won't find nested layers
    return document.layers[objectId];
    } else {
    return false;
    }
} // getObject

function Init()
{
    //var w = document.body.scrollWidth;
    var w = document.body.clientWidth;
    //var h = document.body.scrollHeight;
    var h = document.body.clientHeight;
    
    getObject("tabTree").style.height = h-90;    
    getObject("divHRTree").style.height=h-100;
}

    </script>

 

 当然，仅有客户端的代码是不够的。我们还需要在服务器端构造一棵树。最简单的方法就是从工具箱——〉导航　中将一个ＴｒｅｅＶｉｅｗ控件拖到页面上。在ＴｒｅｅＶｉｅｗ的属性——〉行为中的“ShowCheckBox”一项改为“all”，这样，一个带有CheckBox的树就构造成功了。在服务器端的Page_Load下加入代码：

 if (!Page.IsPostBack)
            {
                //转入前台的 OnTreeNodeChecked()
                TreeView1.Attributes.Add("onclick", "OnTreeNodeChecked()");
             }

 http://www.cnblogs.com/daniel206/archive/2007/08/29/874832.html