做專案時發現有的樹節點名稱太長，想擷取制定長度顯示，其餘用"..."省略顯示，仔細翻閱一下ztree文件發現ztree提供了一個addDiyDom方法，這不就是自己想找的diy dom方法嗎，發現ztree果然強大。

1.首先不要忘記在view中配置addDiy:addDiyDom

view: {
			showLine: false,
			showIcon: false,
			selectedMulti: false,
			dblClickExpand: false,
			addDiyDom: addDiyDom
		},

function addDiyDom(treeId, treeNode) {
		var spaceWidth = 5;
		var switchObj = $("#" + treeNode.tId + "_switch"),
		icoObj = $("#" + treeNode.tId + "_ico");
		switchObj.remove();
		icoObj.before(switchObj);

		if (treeNode.level > 1) {
			var spaceStr = "<span style='display: inline-block;width:" + (spaceWidth * treeNode.level)+ "px'></span>";
			switchObj.before(spaceStr);
		}
		var spantxt=$("#" + treeNode.tId + "_span").html();
		if(spantxt.length>17){
			spantxt=spantxt.substring(0,17)+"...";
			$("#" + treeNode.tId + "_span").html(spantxt);
		}
 

	}