JSTree添加節點到子節點

我正在使用JSTree的MVC項目，我試圖將子節點添加到樹，但是我得到一個空的參考錯誤對象引用未設置爲線上的對象的實例subGroupNode.children.Add(itemNode);我想這是因爲subGroupNode.Children是空的。在之前的foreach循環中創建孩子的時候怎麼會這樣呢？JSTree添加節點到子節點

public JsonResult GetJsTree3Data() 
    { 
     var marketGroups = new List<JsTree3Node>(); 

     // Create our root node and ensure it is opened 
     var root = new JsTree3Node() 
     { 
      id = Guid.NewGuid().ToString(), 
      text = "Market Items", 
      state = new State(true, false, false) 
     }; 

     foreach (var group in GenerateGroups(connString)) 
     { 
      if (group.marketParentGroup == 0) 
      { 
       var node = JsTree3Node.NewNode(group.id_str); 
       node.text = group.name; 
       node.state = new State(false, false, false); 
       marketGroups.Add(node); 
      } 
     } 

     foreach (var marketGroup in marketGroups) 
     { 
      foreach (var subGroup in GenerateGroups(connString)) 
      { 
       if (subGroup.marketParentGroup.ToString() == marketGroup.id) 
       { 
        var childNodes = new List<JsTree3Node>(); 

        var childNode = new JsTree3Node(); 
        childNode.id = subGroup.id_str; 
        childNode.text = subGroup.name; 
        childNode.state = new State(false, false, false); 

        childNodes.Add(childNode); 

        var subGroupNode = new JsTree3Node(); 
        subGroupNode.id = subGroup.id_str; 
        subGroupNode.text = subGroup.name; 
        subGroupNode.state = new State(false, false, false); 
        subGroupNode.children = childNodes; 

        marketGroup.children.Add(subGroupNode); 
       } 
      } 
     } 

     return Json(root, JsonRequestBehavior.AllowGet); 
    }

來源

2017-01-02 Grey Walker

我沒有看到你加'children'屬性'subGroupNode'對象 –

感謝replyng尼古拉，我以爲我是在添加行'subGroupNode.children.Add（itemNode）的subChildNode;' –

因此，在使用'Add'方法（我相信數組方法）之前，您應該先創建該屬性並在其中分配一個空數組？至少這是如何在JavaScript中工作。 –

我創建第二個名單一樣的第一和比較這兩個清單解決問題。

public JsonResult GetJsTree3Data() 
    { 
     var marketGroups = new List<JsTree3Node>(); 
     var marketSubGroups = new List<JsTree3Node>(); 

     foreach (var group in GenerateGroups(connString)) 
     { 
      var node = JsTree3Node.NewNode(group.id_str); 
      node.text = group.name; 
      node.state = new State(false, false, false); 
      node.parentId = group.marketParentGroup; 
      marketSubGroups.Add(node); 
     } 

     // Create our root node and ensure it is opened 
     var root = new JsTree3Node() 
     { 
      id = Guid.NewGuid().ToString(), 
      text = "Market Items", 
      state = new State(true, false, false) 
     }; 

     foreach (var group in marketSubGroups) 
     { 
       var node = JsTree3Node.NewNode(group.id); 
       node.text = group.text; 
       node.state = new State(false, false, false); 
       marketGroups.Add(node); 
     } 

     foreach (var marketGroup in marketGroups) 
     { 
      foreach (var subGroup in marketSubGroups) 
      { 
       if (subGroup.parentId.ToString() == marketGroup.id) 
       { 
        var subGroupNode = new JsTree3Node(); 
        subGroupNode.id = subGroup.id; 
        subGroupNode.text = subGroup.text; 
        subGroupNode.state = new State(false, false, false); 
        marketGroup.children.Add(subGroupNode); 
       } 
      } 
     } 

     root.children = marketGroups; 

     return Json(root, JsonRequestBehavior.AllowGet); 
    }

來源

2017-01-07 00:36:37

JSTree添加節點到子節點

回答

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