JS对象：迭代到第n级

Question

I have the following sample object:

{
   "sampleA":{
      "sampleB1":{
         "sampleC1":{
            "sample1":"sample",
            "sample2":"sample",
            "sample3":"sample",
            "sample4":"sample",
            "sample5":"sample"
         },
         "sampleB2":{
            "sample1":"sample",
            "sample2":"sample sample",
            "sample3":"sample",
            "sample4":"sample sample",
            "sample5":"sample sample",
            "sample6":"sample"
         },
         "sampleB3":{
            "sample1":"sample",
            "sample2":"sample sample",
            "sample3":"sample sample",
            "sample4":"sample sample",
            "sample5":{
               "sample6":"sample",
               "sample7":"sample sample",
               "sample8":"sample sample",
               "sample9":"sample sample",
               "sample10":"sample",
               "sample11":"sample"
            },
            "sample100":"sample"
         }
      }
   }
}

It's a JS object that can be nested up to any level. I'm trying to iterate through the object and do some action:

Following is my code:

function isLeafNode(node) {
  if (typeof node == typeof "string") {
    return true;
  } else {
    return false;
  }
}

iterateObject(jsonData);

function iterateObject(obj) {
  for (var key in jsonData) {
    if (jsonData.hasOwnProperty(key)) {
      if(!isLeafNode(jsonData[key])){
        iterateObject(jsonData[key])
      }else{
        console.log("leaf node")
        //do something
      }
    }
  }
}

But the above code results in an infinite loop. What am I doing wrong?

Answer 1

You need to reference the local obj inside of iterateObject instead of the global jsonData .

 function iterateObject(obj) { for (var key in obj) { if (obj.hasOwnProperty(key)) { if (!isLeafNode(obj[key])) { iterateObject(obj[key]); } else { console.log(key, "leaf node"); } } } } function isLeafNode(node) { return typeof node === "string"; } var data = { sampleA: { sampleB1: { sampleC1: { sample1: "sample", sample2:"sample", sample3:"sample", sample4:"sample", sample5:"sample" },sampleB2: { sample1: "sample", sample2:"sample sample", sample3:"sample", sample4:"sample sample", sample5:"sample sample", sample6:"sample" },sampleB3: { sample1: "sample", sample2:"sample sample", sample3:"sample sample", sample4:"sample sample", sample5:{ sample6: "sample", sample7:"sample sample", sample8:"sample sample", sample9:"sample sample", sample10:"sample", sample11:"sample" },sample100: "sample" } } } }; iterateObject(data); 

 .as-console-wrapper { max-height: 100% !important; top: 0; } 

Answer 2

There is an issue in your below function

function iterateObject(obj) {
  for (var key in jsonData) {
    if (jsonData.hasOwnProperty(key)) {
      if(!isLeafNode(jsonData[key])){
        iterateObject(jsonData[key])
      }else{
        console.log("leaf node")
        //do something
      }
    }
  }
}

It should be like below

function iterateObject(obj) {
  for (var key in obj) {
    if (obj.hasOwnProperty(key)) {
      if(!isLeafNode(obj[key])){
        iterateObject(obj[key])
      }else{
        console.log("leaf node")
        //do something
      }
    }
  }
}

You are using jsonData in loop instead of passed argument obj