Question

我有一个这样的对象：

    var structure = {
    "root":{
        "name":"Main Level",
        nodes:{
            "node1":{
                "label":"Node 1"  
            },
            "node2":{
                "label":"Node 2",
                "selected": true
            },
            "node3":{
                "label":"Node 3"  
            }
        }
    }
}

在javascript中如何在对象中搜索选中：true＆＃39;，并获取其上方的标签值，即＆＃34;节点2＆＃34;

Answer 1

您想要使用for循环。

var nodes = structure.roots.nodes;
var nodeYouWant;
for (var obj in nodes){
   if (nodes[obj].selected == true){
      nodeYouWant = obj;  // Now "node2"
   }
}

Answer 2

您可以遍历structure.root.nodes的密钥（可以使用Object.keys获取）并检查该密钥的节点对象是否为selected。出于本演示的目的，我只记录了选定的node.label。

＆＃13;

var structure = {
  "root": {
    "name": "Main Level",
    nodes: {
      "node1": {
        "label": "Node 1"
      },
      "node2": {
        "label": "Node 2",
        "selected": true
      },
      "node3": {
        "label": "Node 3"
      }
    }
  }
}

var nodes = structure.root.nodes,
    keys = Object.keys(nodes)

for (var i = 0; i < keys.length; i++) {
  var node = nodes[keys[i]]
  if (node.selected) {
    console.log("Selected:", node.label)
    break;
  }
}

＆＃13;

Answer 3

for (n in structure.root.nodes) {
  if (structure.root.nodes[n].selected) {
    console.log("the node which is selected is: " + n); 
  }
}

Answer 4

这将以递归方式遍历您的对象，查找所选值，如果找到则返回密钥名称。

＆＃13;

const structure = {
  "root": {
    "name": "Main Level",
    nodes: {
      "node1": {
        "label": "Node 1"
      },
      "node2": {
        "label": "Node 2",
        "selected": true
      },
      "node3": {
        "label": "Node 3"
      }
    }
  }
}

const findSelected = (obj, ret = '') => {
  for (let key in obj) {
    if (obj[key].selected) {
      return key
    }
    if (obj[key].constructor === Object) {
      ret = findSelected(obj[key])
      if (ret) return ret
    }
  }
}

console.log(
  findSelected(structure) 
)

＆＃13;

Answer 5

也许你可以尝试以下方式。

var structure = {
    "root": {
        "name": "Main Level",
        nodes: {
            "node1": {
                "label": "Node 1"
            },
            "node2": {
                "label": "Node 2",
                "selected": true
            },
            "node3": {
                "label": "Node 3"
            }
        }
    }
};
let nodes = structure.root.nodes;
Object.keys(nodes).forEach(key => {
    if(nodes[key].selected === true){
        //do something like below
        //console.log(nodes[key].label);
    }
});

参考：https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/keys

Javascript对象获得上面的值

5 个答案: