JavaScript的按價值計算深嵌套對象/數組找到

Question

你好，我在我的函數返回一個對象的問題，比方說，我有一個對象：

var elements = [{ 
    "fields": null, 
    "id_base": "nv_container", 
    "icon": "layout", 
    "name": "container", 
    "is_container": true, 
    "elements" : [ 
     //another elements set here 
    ] 
}, 
{ 
    "id_base": "novo_example_elementsec", 
    "name": "hello", 
    "icon": "edit", 
    "view": {} 
}]; 

我想要的是一個函數（在純JavaScript），可以找到一個特定的鍵和值的對象，我已經創建了一個函數，但它只是不能正常工作？ ，我的功能：

function findNested(obj, key, value) { 
    //Early return 
    if (obj[key] === value) { 
     console.log('before return'); //until here . its fine 
     return obj; //not working 
    } else { 
     for (var i = 0, len = Object.keys(obj).length; i <= len; i++) { 
      if (typeof obj[i] == 'object') { 
       this.findNested(obj[i] , key, value); 
      } 
     } 
    } 
} 

我只是不明白我做錯了什麼？

謝謝。

Answer 1

您在遞歸調用後錯過了返回。如果在遞歸之後找到該對象，則需要繼續冒泡該結果（通過返回它）。正如@ scott-marcus指出的那樣，您還應該使用i < len（而不是i <= len）。

var elements = [{ 
 
    "fields": null, 
 
    "id_base": "nv_container", 
 
    "icon": "layout", 
 
    "name": "container", 
 
    "is_container": true, 
 
    "elements": [ 
 
     //another elements set here 
 
    ] 
 
    }, 
 
    { 
 
    "id_base": "novo_example_elementsec", 
 
    "name": "hello", 
 
    "icon": "edit", 
 
    "view": {} 
 
    } 
 
]; 
 

 
function findNested(obj, key, value) { 
 
    // Base case 
 
    if (obj[key] === value) { 
 
    return obj; 
 
    } else { 
 
    for (var i = 0, len = Object.keys(obj).length; i < len; i++) { 
 
     if (typeof obj[i] == 'object') { 
 
     var found = this.findNested(obj[i], key, value); 
 
     if (found) { 
 
      // If the object was found in the recursive call, bubble it up. 
 
      return found; 
 
     } 
 
     } 
 
    } 
 
    } 
 
} 
 

 
console.log(findNested(elements, "icon", "layout")); // returns object 
 
console.log(findNested(elements, "icon", "edit")); // returns object 
 
console.log(findNested(elements, "foo", "bar")); // returns undefined