Treeview 只展開一個節(jié)點,其他節(jié)點關(guān)閉

yhb4000 2012-04-05

展開全文

asp.net 2.0 的 TreeView 控件功能雖說強大,但其客戶端控制很遜色,本文將講解 TreeView 的客戶端實現(xiàn)原理,并實現(xiàn)兩個個性化操作：
(1) 節(jié)點的全部打開和關(guān)閉；
Client Side Expand/Collapse All Nodes For ASP.NET 2.0 TreeView.
(2) 只打開一個節(jié)點(關(guān)閉其他兄弟節(jié)點)。
Just one expanded node in ASP.NET 2.0 TreeView (When a client expand one node all other will collaps)
用記事本打開頁面源代碼，可以找到一下兩個腳本引用：

將"/WebUI/WebResource.axd?d=RAQeBcDUNuP9iuS8q3tNEw2&t=633300220640000000"拷到地址欄尾，下載腳本，并以 .js 命名，另一個同樣操作。分析第二個腳本文件，可以看到TreeView的很多客戶端函數(shù)，其中關(guān)鍵的一個 TreeView_ToggleNode 就是客戶端點擊時觸發(fā)的事件。
要想做個性化的操作，就得從 TreeView_ToggleNode 事件下手。我們無法更改.net封裝好的腳本，只有“重寫”。所謂的重寫就是在原來的函數(shù)之后添加一個同名函數(shù)（因為js對于同名函數(shù)只調(diào)用最后一個）。

TreeView_ToggleNode 的原函數(shù)：

function TreeView_ToggleNode(data, index, node, lineType, children) {
    var img = node.childNodes[0];
    var newExpandState;
    try {
        if (children.style.display == "none") {
            children.style.display = "block";
            newExpandState = "e";
            if ((typeof(img) != "undefined") && (img != null)) {
                if (lineType == "l") {
                    img.src = data.images[15];
                }
                else if (lineType == "t") {
                    img.src = data.images[12];
                }
                else if (lineType == "-") {
                    img.src = data.images[18];
                }
                else {
                    img.src = data.images[5];
                }
                img.alt = data.collapseToolTip.replace(/\{0\}/, TreeView_GetNodeText(node));
            }
        }
        else {
            children.style.display = "none";
            newExpandState = "c";
            if ((typeof(img) != "undefined") && (img != null)) {
                if (lineType == "l") {
                    img.src = data.images[14];
                }
                else if (lineType == "t") {
                    img.src = data.images[11];
                }
                else if (lineType == "-") {
                    img.src = data.images[17];
                }
                else {
                    img.src = data.images[4];
                }
                img.alt = data.expandToolTip.replace(/\{0\}/, TreeView_GetNodeText(node));
            }
        }
    }
    catch(e) {}
    data.expandState.value = data.expandState.value.substring(0, index) + newExpandState + data.expandState.value.slice(index + 1);
}
1. 節(jié)點的全部打開和關(guān)閉(Client Side Expand/Collapse All Nodes)
<html xmlns="http://www./1999/xhtml">
<head runat="server">
    <title>LeftMenu_Tree</title>
</head>
<body bgcolor="#DDEDFD">
    <form id="form1" runat="server">
        <a href="javascript:TreeviewExpandCollapseAll('<%=TreeView1.ClientID%>', true)">Expand
            All</a> <a href="javascript:TreeviewExpandCollapseAll('<%=TreeView1.ClientID%>', false)">
                Collapse All</a>
        <asp:TreeView ID="TreeView1" SkinID="tvClass" runat="server" ShowLines="true" NodeWrap="false">
        </asp:TreeView>
    </form>
</body>
</html>

function GetParentByTagName(parentTagName, childElementObj)
{
    var parent = childElementObj.parentNode;
    while(parent.tagName.toLowerCase() != parentTagName.toLowerCase())
    {
        parent = parent.parentNode;
    }
    return parent;
}
//-----------------------------------------------------------------------------
</script>

2. 只打開一個節(jié)點,關(guān)閉其他兄弟節(jié)點(Just one expanded node, all other will collaps) <html xmlns="http://www./1999/xhtml">
<head runat="server">
    <title>LeftMenu_Tree</title>
</head>
<body bgcolor="#DDEDFD">
    <form id="form1" runat="server">
        <a href="javascript:TreeviewExpandCollapseAll('<%=TreeView1.ClientID%>', true)">Expand
            All</a> , <a href="javascript:TreeviewExpandCollapseAll('<%=TreeView1.ClientID%>', false)">
                Collapse All</a>
        <asp:TreeView ID="TreeView1" SkinID="tvClass" runat="server" ShowLines="true" NodeWrap="false">
        </asp:TreeView>
    </form>
</body>
</html>

//折疊兄弟節(jié)點(Collapse Brothers)
function CollapseBrothers(data,childContainer)
{
    var parent = childContainer.parentNode;
    for(i=0; i< parent.childNodes.length; i++)
    {
        if(parent.childNodes[i].tagName.toLowerCase() =="div")
        {
            if(parent.childNodes[i].id != childContainer.id)
            {
                parent.childNodes[i].style.display = "none"
            }
        }
        else if(parent.childNodes[i].tagName.toLowerCase() =="table")
        {
            var treeLinks = parent.childNodes[i].getElementsByTagName("a");
            if(treeLinks.length > 2)
            {
                var j=0;
                if(treeLinks[j].firstChild.tagName)
                {
                    if(treeLinks[j].firstChild.tagName.toLowerCase() == "img")
                    {
                        var img = treeLinks[j].firstChild;
                        if(i==0)
                            img.src = data.images[8];
                        else if(i==parent.childNodes.length-2)
                            img.src = data.images[14];
                        else
                            img.src = data.images[11];
                    }
                }
            }
        }
    }
}
//-----------------------------------------------------------------------------
</script>