Question

这是我的json ::

[{ “名字”：“罗伊”， “城市”：“达拉斯”， “州”：“德州” }，{ “名字”：“卡拉”， “城市”：“洛杉矶”， “州”：“加州” }，{ “名字”：“菲利克斯”， “城市”：“拉斯维加斯”， “州”：“内华达” }，{ “名字”：“弗雷德”， “城市”：“迈阿密”， “州”：“佛罗里达州” }，{ “名字”：“比尔”， “城市”：“亚特兰大”， “州”：“格鲁吉亚” }，{ “名字”：“迈克”， “城市”：“芝加哥”， “州”：“伊利诺伊州” }，{ “名字”：“蒂姆”， “城市”：“伍斯特”， “州”：“MA” }，{ “名字”：“瑞恩”， “城市”：“奥斯汀”， “州”：“德州” }，{ “名字”：“山姆”， “城市”：“波士顿”， “州”：“MA” }，{ “名字”：“莎拉”， “城市”：“休斯顿”， “州”：“德州” }]

我希望捕获德克萨斯州的所有索引号：

请帮忙。

Answer 1

您可以使用map()和filter()等方法。

var data = [{ "name": "Roy", "city": "Dallas", "state": "Texas" }, { "name": "Karla", "city": "LA", "state": "California" },{ "name": "Felix", "city": "Las Vegas", "state": "Nevada" },{ "name": "Fred", "city": "Miami", "state": "Florida" },{ "name": "Bill", "city": "Atlanta", "state": "Georgia" },{ "name": "Mike", "city": "Chicago", "state": "Illinois" },{ "name": "Tim", "city": "Worcester", "state": "MA" },{ "name": "Ryan", "city": "Austin", "state": "Texas" },{ "name": "Sam", "city": "Boston", "state": "MA" },{ "name": "Sarah", "city": "Houston", "state": "Texas" }];

var indexes = data.map(function(item, i){
    if(item.state == "Texas") return i;
}).filter(function(item){ return item!=undefined; });

console.log(indexes);

Answer 2

您可以在收集匹配状态的索引时使用Array#reduce。

var array = [{ name: "Roy", city: "Dallas", state: "Texas" }, { name: "Karla", city: "LA", state: "California" }, { name: "Felix", city: "Las Vegas", state: "Nevada" }, { name: "Fred", city: "Miami", state: "Florida" }, { name: "Bill", city: "Atlanta", state: "Georgia" }, { name: "Mike", city: "Chicago", state: "Illinois" }, { name: "Tim", city: "Worcester", state: "MA" }, { name: "Ryan", city: "Austin", state: "Texas" }, { name: "Sam", city: "Boston", state: "MA" }, { name: "Sarah", city: "Houston", state: "Texas" }],
    indices = array.reduce((r, o, i) => (o.state === 'Texas' && r.push(i), r), []);

console.log(indices);

Answer 3

这是你需要的吗？

var obj=[{ "name": "Roy", "city": "Dallas", "state": "Texas" }, { "name": "Karla", "city": "LA", "state": "California" },{ "name": "Felix", "city": "Las Vegas", "state": "Nevada" },{ "name": "Fred", "city": "Miami", "state": "Florida" },{ "name": "Bill", "city": "Atlanta", "state": "Georgia" },{ "name": "Mike", "city": "Chicago", "state": "Illinois" },{ "name": "Tim", "city": "Worcester", "state": "MA" },{ "name": "Ryan", "city": "Austin", "state": "Texas" },{ "name": "Sam", "city": "Boston", "state": "MA" },{ "name": "Sarah", "city": "Houston", "state": "Texas" }],
indexes=[];

for(var index in obj){
  if(obj[index]['state']=='Texas')
    indexes.push(index);
}

console.log(indexes);

Answer 4

您可以枚举集合并在数组中添加索引，其中state为“Texas”。如果使用服务器端代码，则可以使用JSON解析器对响应（对包含与JSON对象相同的属性的目标类型）进行反序列化。如果您使用的是Javascript，则可以将JSON.parse（jsonString）转换为对象数组，然后枚举

Answer 5

您可以使用for循环来实现此目的。迭代一个变量，比如'i'，会很有用。

texas_indecies = [];
for (var i = 0; i < array.length; i++){
  if (array[i].state == "Texas"){
    texas_indecies.push(i);
  }
}

获取json数组

5 个答案: