再帰的探索でオブジェクト ツリーをトラバースして操作する方法

<code class="javascript">for (var key in foo) {
  if (key == "child") {
    // Implement the desired action for the 'child' property.
  }
}</code>

<code class="javascript">for (var key in foo) {
  if (!foo.hasOwnProperty(key)) {
    continue; // Ignore inherited properties.
  }
  if (key == "child") {
    // Perform the intended action for the 'child' property.
  }
}</code>

<code class="javascript">function eachRecursive(obj) {
  for (var k in obj) {
    if (typeof obj[k] == "object" && obj[k] !== null) {
      eachRecursive(obj[k]); // Recursively explore nested objects.
    } else {
      // Execute the desired action for non-object properties.
    }
  }
}</code>