Question

我有一个从Web服务返回的JSON对象，我想从对象中提取元素，特别是第一个元素id？

[{"id":2,"type":"Asset",
  "assetNumber":"13723",
  "macAddress":null,"networkName":
  "13723imsmid8","model": 
 {"id":16,"type":"Model",
  "modelName":"M73","manufacturer":
 {"id":10,"type":"Manufacturer"}}}, 
 {"id":3556,"type":"Asset",
  "assetNumber":"13723",
  "macAddress":null,
  "networkName":null,
  "model":{"id":16,"type":"Model",
  "modelName":"M73","manufacturer":
 {"id":10,"type":"Manufacturer"}}}, 
 {"id":7196,"type":"Asset",
  "assetNumber":"13723",
  "macAddress":null,"networkName":null,
  "model":{"id":16,"type":"Model",
  "modelName":"M73","manufacturer":
  {"id":10,"type":"Manufacturer"}}},
  {"id":9720,"type":"Asset", 
   "assetNumber":"13723",
   "macAddress":null,"networkName":null,
   "model":{"id":16,"type":"Model","modelName":"M73",
   "manufacturer": {"id":10,"type":"Manufacturer"}}},
  {"id":11689,"type":"Asset",
   "assetNumber":"13723",
   "macAddress":null,
   "networkName":null,"
    model":{"id":68,"type":"Model",
    "modelName":"POC-W211","manufacturer": 
   {"id":19,"type":"Manufacturer"}}},{"id":11906,"type":"Asset",
    "assetNumber":"13723",
    "macAddress":null,
    "networkName":null,
    "model":{"id":71,"type":"Model",
    "modelName":"OptiPlex 780",
    "manufacturer":{"id":5,"type":"Manufacturer"}}}]

Answer 1

您可以迭代数据数组并使用数组映射函数提取ID：

const data = [{"id":2,"type":"Asset","assetNumber":"13723","macAddress":null,"networkName":"13723imsmid8","model":{"id":16,"type":"Model","modelName":"M73","manufacturer":{"id":10,"type":"Manufacturer"}}},{"id":3556,"type":"Asset","assetNumber":"13723","macAddress":null,"networkName":null,"model":{"id":16,"type":"Model","modelName":"M73","manufacturer":{"id":10,"type":"Manufacturer"}}},{"id":7196,"type":"Asset","assetNumber":"13723","macAddress":null,"networkName":null,"model":{"id":16,"type":"Model","modelName":"M73","manufacturer":{"id":10,"type":"Manufacturer"}}},{"id":9720,"type":"Asset","assetNumber":"13723","macAddress":null,"networkName":null,"model":{"id":16,"type":"Model","modelName":"M73","manufacturer":{"id":10,"type":"Manufacturer"}}},{"id":11689,"type":"Asset","assetNumber":"13723","macAddress":null,"networkName":null,"model":{"id":68,"type":"Model","modelName":"POC-W211","manufacturer":{"id":19,"type":"Manufacturer"}}},{"id":11906,"type":"Asset","assetNumber":"13723","macAddress":null,"networkName":null,"model":{"id":71,"type":"Model","modelName":"OptiPlex 780","manufacturer":{"id":5,"type":"Manufacturer"}}}];

const ids = data.map(item => item.id)
// returns an array of ids: [2, 10, 16, ...]

Answer 2

或者，

var json = [{"id":2,"type":"Asset","assetNumber":"13723","macAddress":null,"networkName":"13723imsmid8","model":{"id":16,...';
var p = 0;
do {
    p=json.indexOf('"id":',p)+5;
    n=json.indexOf(',',p);
    alert(json.substr(p,(n-p)));
} 
while (json.indexOf('"id":',p)>0);

如何从Web服务中获取JSON中的元素

2 个答案: