diff --git a/JavaScript/4-newfunc.js b/JavaScript/4-newfunc.js
new file mode 100644
index 0000000..d864d7a
--- /dev/null
+++ b/JavaScript/4-newfunc.js
@@ -0,0 +1,78 @@
+'use strict';
+
+function Node(parent, name, data) {
+  this.name = name;
+  this.data = data;
+  if (parent) {
+    this.parent = parent;
+    parent[name] = this;
+  }
+  this.child = [];
+}
+
+function Tree(name, data) {
+  this.root = new Node(null, name, data);
+}
+
+Tree.prototype.visitDepth = function(callback) {
+
+  (function recursive(currNode) {
+
+    const len = currNode.child.length;
+    let num;
+    for (num = 0; num < len; ++num) {
+      recursive(currNode.child[num]);
+    }
+
+    callback(currNode);
+  })(this.root);
+};
+
+Tree.prototype.isHave = function(callback) {
+  this.visitDepth.call(this, callback);
+};
+
+Tree.prototype.addData = function(name, data, whereAdd) {
+  let parent = null;
+  const callback = function(n) {
+    if (n.name === whereAdd) {
+      parent = n;
+    }
+  };
+  this.isHave(callback);
+
+  const node = new Node(parent, name, data);
+  if (parent) {
+    parent.child.push(node);
+    node.parent = parent;
+  } else {
+    throw new Error('Parent not exist!');
+  }
+};
+
+
+const tree = new Tree('one', 1);
+
+tree.root.child.push(new Node(tree, 'two', 2));
+
+tree.root.child.push(new Node(tree, 'three', 3));
+
+tree.root.child.push(new Node(tree, 'four', 4));
+
+tree.root.child[0].child.push(new Node(tree.root.child[0], 'five', 5));
+
+tree.root.child[0].child.push(new Node(tree.root.child[0], 'six', 6));
+
+tree.root.child[2].child.push(new Node(tree.root.child[2], 'seven', 7));
+
+
+tree.isHave(n => {
+  if (n.name === 'five') {
+    console.dir(n);
+  }
+});
+
+tree.visitDepth(n => console.dir(n));
+
+tree.addData('qwe', 456, 'two');
+console.dir(tree);