JavaScript-如何像變數一樣參考JSON中的專案？

考慮我有以下變數：

var result = {
    "Items": [
      {
        "location": "New York",
        "visible": false,
        "destinations": [
          4,
          3,
          5
        ],
        "id": 3,
        "coordinates": {
          "lng": -74.17,
          "lat": 40.68
        }
      },{
        "location": "Madrid",
        "visible": false,
        "destinations": [
          0,
          4
        ],
        "id": 0,
        "coordinates": {
          "lng": -3.56,
          "lat": 40.49
        }
      },
      {
        "location": "Los Angeles",
        "visible": false,
        "destinations": [
          4,
          3,
          5
        ],
        "id": 5,
        "coordinates": {
          "lng": -118.4,
          "lat": 33.94
        }
      }
    ]
  };

如果我想參考洛杉磯，我會這樣做，而且效果很好：

  console.log(result.Items[2]);

如果我不知道訂單但我知道它的 id (5) 怎么辦。如何通過其 ID 參考它？

uj5u.com熱心網友回復：

你不能直接參考它，但是你可以在陣列上使用一些Javascript函式來找到它，比如：

result.Items.find(x => x.id == 5);

參考：https : //developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/find

uj5u.com熱心網友回復：

像這樣過濾你的輸入

let newFilteredArray = result.filter(item => {
    return item.id === 5;
};
console.log(newFilteredArray[0];

uj5u.com熱心網友回復：

你可以做

var result = {
    "Items": [
      {
        "location": "New York",
        "visible": false,
        "destinations": [
          4,
          3,
          5
        ],
        "id": 3,
        "coordinates": {
          "lng": -74.17,
          "lat": 40.68
        }
      },{
        "location": "Madrid",
        "visible": false,
        "destinations": [
          0,
          4
        ],
        "id": 0,
        "coordinates": {
          "lng": -3.56,
          "lat": 40.49
        }
      },
      {
        "location": "Los Angeles",
        "visible": false,
        "destinations": [
          4,
          3,
          5
        ],
        "id": 5,
        "coordinates": {
          "lng": -118.4,
          "lat": 33.94
        }
      }
    ]
  };


    var array = JSON.parse(JSON.stringify(result));
        



    var result = {
        "Items": [
          {
            "location": "New York",
            "visible": false,
            "destinations": [
              4,
              3,
              5
            ],
            "id": 3,
            "coordinates": {
              "lng": -74.17,
              "lat": 40.68
            }
          },{
            "location": "Madrid",
            "visible": false,
            "destinations": [
              0,
              4
            ],
            "id": 0,
            "coordinates": {
              "lng": -3.56,
              "lat": 40.49
            }
          },
          {
            "location": "Los Angeles",
            "visible": false,
            "destinations": [
              4,
              3,
              5
            ],
            "id": 5,
            "coordinates": {
              "lng": -118.4,
              "lat": 33.94
            }
          }
        ]
      };


        var array = JSON.parse(JSON.stringify(result));
            
            for (i=0;i<=array.Items.length-1;i  ){
                if (array.Items[i].id == 5) {
                    console.log(array.Items[i])
                }
            }
 Run code snippetHide resultsExpand snippet

uj5u.com熱心網友回復：

var id = 2

您可以將 id 設定為與 index 和 console.log(result.Items[id]) 示例相同：

var result = {
    "Items": [
      {
        "location": "New York",
        "visible": false,
        "destinations": [
          4,
          3,
          5
        ],
        "id": 0,
        "coordinates": {
          "lng": -74.17,
          "lat": 40.68
        }
      },{
        "location": "Madrid",
        "visible": false,
        "destinations": [
          0,
          4
        ],
        "id": 1,
        "coordinates": {
          "lng": -3.56,
          "lat": 40.49
        }
      },
      {
        "location": "Los Angeles",
        "visible": false,
        "destinations": [
          4,
          3,
          5
        ],
        "id": 2,
        "coordinates": {
          "lng": -118.4,
          "lat": 33.94
        }
      }
    ]
  };

標籤：javascript

上一篇：將環境變數與GoogleKubernetesEngine一起使用（安全、簡單且良好的實踐）？

下一篇：如何解決“T”可以用與“T[]”無關的任意型別實體化的問題？