Question

我有一个JSON对象，如下面的

{
 "db": {
 "name": "db",
 "connector": "memory"
  },
"MySql": {
   "host": "localhost",
   "port": 3306,
   "database": "users",
   "username": "root",
   "password": "",
   "name": "MySql",
   "connector": "mysql"
  },
"postgreDS": {
   "host": "localhost", 
   "port": 1234,
   "database": "abc", 
   "username": "postgres", 
   "password": "abc",
   "name": "postgreDS",
   "connector": "postgresql"
 }

我需要此对象的以下输出。

{"db", "MySql", "postgreDS"}

我应该如何从JavaScript中的整个JSON对象中提取上述信息。以及我将如何读取子键和值。

Answer 1

像这样（其中obj是你的JSON对象）：

var objectProperties = [];
for(var prop in obj){
    objectProperties.push(prop);
}
console.log(JSON.stringify(objectProperties)); // ["db", "MySql", "postgreDS"]

Answer 2

如果您只想获取嵌套对象的键，请使用Object.keys：

var keys = Object.keys(obj); // [ "db", "MySql", "postgreDS" ]

如果您希望根据指定的键从嵌套对象中获取值，这里将返回一个返回值数组的泛型函数：

function getValueFromKey(obj, key) {
    return Object.keys(obj).map(function (el) {
        return obj[el][key];
    });
}

getValueFromKey(obj, 'name'); // [ "db", "MySql", "postgreDS" ]
getValueFromKey(obj, 'connector'); // [ "memory", "mysql", "postgresql" ]

c++11

Answer 3

尝试FIDDLE，

的javascript

$(function(){
var output = {};
var items = {
 "db": {
 "name": "db",
 "connector": "memory"
  },
"MySql": {
   "host": "localhost",
   "port": 3306,
   "database": "users",
   "username": "root",
   "password": "",
   "name": "MySql",
   "connector": "mysql"
  },
"postgreDS": {
   "host": "localhost", 
   "port": 1234,
   "database": "abc", 
   "username": "postgres", 
   "password": "abc",
   "name": "postgreDS",
   "connector": "postgresql"
 }};

for(var propertyName in items) {
    output.push(propertyName); // output will have the required output

}
console.log(output);
});

如何以自定义方式读取JSON文件

3 个答案: