JS forest leaf node non recursive depth first postorder traversal

afterPreview(trees) {
    let nodeList = [].concat(trees);
    while (nodeList.length > 0) {
        let currentNode = nodeList.pop();
        if (currentNode.hasOwnProperty("children")) {
            nodeList = nodeList.concat(currentNode.children);
        }
        else {
            // Here is the leaf node 
            this.dataUpload(currentNode);
        }
    }
    this.showUpdateFlag = true;
    return trees;
}

Please adjust it according to your own data structure .

remarks ：

1. In the above methods

trees The structure is ： [tree1,tree2,tree3]

tree The structure can be abstracted as ：{

    children:[leaf1,leaf2,leaf3]

}

leaf The structure is abstracted as ：{

    ......

}

2. If you want a non leaf node , At the first if Handle under