Function(treeId, treeNodes, targetNode, moveType)setting.callback.beforeDrop

Overview[ depends on jquery.ztree.exedit js ]

Used to capture the event before drag-drop node, zTree based on return value to determine whether to allow drag-drop node.

Default: null

When drop the nodes, if the dragged nodes is not in a valid location, this callback will not triggered, and will restore the original position.

Function Parameter Descriptions

treeIdString

zTree unique identifier: treeId, easy for users to control.

treeNodesArray(JSON)

A collection of the nodes which has been dragged

targetNodeJSON

JSON data object of the target node which treeNodes are drag-dropped.

If the treeNodes will be root node, the targetNode = null

moveTypeString

the relative position of move to the target node

"inner": will be child of targetNode

"prev": will be sibling node, and be in front of targetNode

"next": will be sibling node, and be behind targetNode

Return Boolean

return true or false

If return false, zTree will restore the dragged nodes, and will not trigger the 'onDrop' callback.

Examples of setting & function

1. disable to drag nodes to root

function zTreeBeforeDrop(treeId, treeNodes, targetNode, moveType) {
    return !(targetNode == null || (moveType != "inner" && !targetNode.parentTId));
};
var setting = {
	edit: {
		enable: true
	},
	callback: {
		beforeDrop: zTreeBeforeDrop
	}
};
......