动态编程：返回JavaScript中所有匹配的数据
假设我们有一个JSON对象，其中包含有关某些国家/地区的某些城市的位置的信息，例如：
const countryInfo = {
country: [{
name: "Bangladesh",
province: [{
name:"Dhaka",
city: [{
name:"Tangail",
lat: '11'
}, {
name:"Jamalpur",
lat: '12'
}]
}, {
name: "Khulna",
city: [{
name:"Jossore",
lat: '22'
}, {
name:"Tangail",
lat: '23'
}]
}, {
name: "Rajshahi",
city: [{
name:"Pabna",
lat: '33'
}, {
name:"Rangpur",
lat: '33'
}]
}]
},{
name: "India",
province: [{
name:"West Bengal",
city: [{
name:"Calcutta",
lat: '111'
}, {
name:"Tangail",
lat: '112'
}]
}, {
name: "Uttar Pradesh",
city: [{
name:"Agra",
lat: '122'
}, {
name:"Tajmahal",
lat: '123'
}]
}, {
name: "Rajasthan",
city: [{
name:"Kanpur",
lat: '131'
}, {
name:"Jaypur",
lat: '132'
}]
}]
}]
};我们需要编写一个JavaScript函数，该函数接受一个这样的对象和一个搜索字符串。
然后，我们应该搜索与搜索字符串匹配的所有城市名称，并返回与查询匹配的所有城市对象的数组。
示例
为此的代码将是-
const countryInfo = {
country: [{
name: "Bangladesh",
province: [{
name:"Dhaka",
city: [{
name:"Tangail",
lat: '11'
}, {
name:"Jamalpur",
lat: '12'
}]
}, {
name: "Khulna",
city: [{
name:"Jossore",
lat: '22'
}, {
name:"Tangail",
lat: '23'
}]
}, {
name: "Rajshahi",
city: [{
name:"Pabna",
lat: '33'
}, {
name:"Rangpur",
lat: '33'
}]
}]
},{
name: "India",
province: [{
name:"West Bengal",
city: [{
name:"Calcutta",
lat: '111'
}, {
name:"Tangail",
lat: '112'
}]
}, {
name: "Uttar Pradesh",
city: [{
name:"Agra",
lat: '122'
}, {
name:"Tajmahal",
lat: '123'
}]
}, {
name: "Rajasthan",
city: [{
name:"Kanpur",
lat: '131'
}, {
name:"Jaypur",
lat: '132'
}]
}]
}]
};
const searchForCity = (obj, query) => {
const cities = obj.country.reduce((acc, val) => {
val.province.forEach(el => {
el.city.forEach(elm => {
acc.push(elm);
});
});
return acc;
},[]);
const res = cities.filter(el => {
return el.name === query;
});
return res;
};
console.log(searchForCity(countryInfo, 'Tangail'));输出结果
控制台中的输出-
[
{ name: 'Tangail', lat: '11' },
{ name: 'Tangail', lat: '23' },
{ name: 'Tangail', lat: '112' }
]