## Boolean treeNode.isFirstNode

### Overview[ depends on jquery.ztree.core js ]

Judge whether the node is the sibling nodes's first node.

Do not initialize or modify it, it is created by the zTree.

### Boolean Format

true means: the node is first node.

false means: the node is not first node.

### Examples of treeNode

#### 1. Judge whether the first selected node is the sibling nodes's first node.

    var treeObj = $.fn.zTree.getZTreeObj("tree");
    var sNodes = treeObj.getSelectedNodes();
    if (sNodes.length > 0) {
    	var isFirstNode = sNodes[0].isFirstNode;
    }