D3.js node.children Property

Last Updated : 23 Sep, 2020

The node.children property in D3.js returns an array of child nodes (null for leaf nodes and undefined for nodes having no child).

Syntax:

node.children

Return Value: This property returns an array of child nodes (null for leaf nodes and undefined for nodes having no child).

Example 1:

HTML

<!DOCTYPE html> 
<html> 
<head> 
    <meta charset="utf-8"> 
  
    <script src= 
        "https://d3js.org/d3.v5.min.js"> 
    </script> 
</head> 
  
<body> 
    <script> 
        var data = { 
            "name":"GeeksforGeeks",  
            "about":"Computer Science Portal", 
            "children":[{"name":"GFG"}] 
        } 
        var root = d3.hierarchy(data); 
        console.log(root.children); 
    </script> 
</body> 
  
</html>

Output:

Example 2: In this example, this method returns undefined as the root node has no child node.

HTML

<!DOCTYPE html> 
<html> 
  
<head> 
    <meta charset="utf-8"> 
  
    <script src= 
        "https://d3js.org/d3.v5.min.js"> 
    </script> 
</head> 
  
<body> 
    <script> 
        var data = {"name":"GFG1"} 
  
        var root = d3.hierarchy(data); 
  
        console.log(root.children); 
    </script> 
</body> 
  
</html>