实现树的checkbox 选择操作

 

 <asp:TreeView ID="treeviewTest" runat="server"    PopulateNodesFromClient="true"   ImageSet="xPFileExplorer" OnTreeNodeExpanded="treeviewTest_TreeNodeExpanded"
               onclick="OnTreeNodeChecked(this)"
              >

 //当触发checkbox时触发
     function OnTreeNodeChecked()
    {
    var element = element = window.event.srcElement;
    if (!IsCheckBox(element))
    return;

    var isChecked = element.checked;
    var tree = TV2_GetTreeById("treeviewTest");
   
    var node = TV2_GetNode(tree,element);

    TV2_SetChildNodesCheckStatus(node,isChecked);

    var parent = TV2_GetParentNode(tree,node);
   

    TV2_NodeOnChildNodeCheckedChanged(tree,parent,isChecked);

    }
    //设置checkbox状态，
    function TV2_SetChildNodesCheckStatus(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;
        }
    }  
    //当checkbox 的状态变化时触发
    function TV2_NodeOnChildNodeCheckedChanged(tree,node,isChecked)
    {
   
        if(node == null)
            return;
       
        var childNodes = TV2_GetChildNodes(tree,node);
      

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

        for(var i = 0; i < childNodes.length; i++)
        {
            var item = childNodes[i];
            var value = TV2_NodeGetChecked(item);
          
            if(isChecked != value)
            {
                isAllSame = false;
                break;
            }
        }

        var parent = TV2_GetParentNode(tree,node);
        if(isAllSame)
        {
            TV2_NodeSetChecked(node,isChecked);      
            TV2_NodeOnChildNodeCheckedChanged(tree,parent,isChecked);
        }  
        else
        {  
            TV2_NodeSetChecked(node,false);
            TV2_NodeOnChildNodeCheckedChanged(tree,parent,false);
        }
    }
    //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");
      
        //The structure of node: <table>information of node</table><div>child nodes</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
    }

    function TV2_NodeGetChecked(node)
    {
        var checkbox = TV2i_NodeGetCheckBox(node); 
        return checkbox.checked;
    }

    function TV2_NodeSetChecked(node,isChecked)
    {
        var checkbox = TV2i_NodeGetCheckBox(node);
        if(checkbox != null)
         checkbox.checked = isChecked;
    }

    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);
    }

    //////////////////////////////////////////////////////////////////////////////////////////////
    //private mothods, with TV2i_ prefix
    //////////////////////////////////////////////////////////////////////////////////////////////

    //get div contains child nodes
    function TV2i_GetChildNodesDiv(node)
    {
       
 
        if(!TV2_NodeIsLeaf(node))
            return null;
          
        var childNodsDivId = node.id;
        childNodsDivId = childNodsDivId.substr(0,childNodsDivId.length -8)+ "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); 
    }