Hello Frank you can set NodeStyle for Normal and Over properties. 

E.g In normal state, please try to apply below style.

 <NodeStyle>
 <Normal ForeColor="Blue">
 </Normal>
 <Over ForeColor="Red">
 </Over>
 </NodeStyle>

Regards,
Handy

I am sorry,your idea can not meet my need. I want to chang the current node(e.Node.Depth == 2)when I mousemove(not all the nodes).(see the picture)
can you help me???

Hello Frank,

I am afraid, it is not possible. Your workaround is raised an issue according to your screenshot.
The problem is, text is also applied into table element.
I suggest you to do it via client side by using attachevent for the current node.

Regards,
Handy

Can you show me a demo about how to custom style by clientside???
However,it does not work by the code below:
function WebTreeView1_OnNodeSelect(ctrlId, node) {
    var url = node.Value;
//    alert(node.style)
      node.style.color='red';
    if (url != "") {
        setPanelURL(url);       
    }
    return true;
}

Hello Frank,

It is not possible to change its color in properties. You will need to get the element and set its style.

function WebTreeView1_OnNodeSelect(ctrlId, node) {
    var url = node.Value;
    node.GetElement().style.color="red";
    if (url != "") {
        setPanelURL(url);        
    }
    return true;
}

Regards,
Handy

thank you,Handy

Can I set the style of the selected node?(the other nodes keep the default style)

Hello,

I think it is easier if you configure it in Node Style properties. Selected node would be referred into Active style.

Regards,
Handy