这是我的目标：
var tools = {
hammer: {
name: "hammer",
number: "23",
owner;
"John"
},
screwdriver: {
name: "screwdriver",
number: "72",
owner: "Peter",
},
crowbar: {
name: "crowbar",
number: "6",
owner: "Jack"
}
};
这个函数很好地为我提供了控制台日志中的所有数据：
我的问题是如何只从对象中获取所有者的值？
Object.keys(tools).forEach(function(key) {
console.log(key, items[key]);
});
答案 0 :(得分：1)
如果您只想要所有者名称，请执行此操作，
Object.keys(tools).forEach(function(key) {
console.log(key, tools[key].owner);
});
循环中的tools[key]包含整个对象，当您需要单个属性时，只需使用dot notation引用它
var tools = {
hammer: {
name: "hammer",
number: "23",
owner: "John"
},
screwdriver: {
name: "screwdriver",
number: "72",
owner: "Peter",
},
crowbar: {
name: "crowbar",
number: "6",
owner: "Jack"
}
};
Object.keys(tools).forEach(function(key) {
console.log(key, tools[key].owner);
});
答案 1 :(得分：0)
在forEach回调中，使用tools代替items。您的问题中的代码没有分配给items的任何内容，因此无法按预期工作。
通过owner
tools[key]中的tools[key].owner媒体资源
如果您只想记录所有者名称，则可以从key,中删除console.log。
var tools = {
hammer: {
name: "hammer",
number: "23",
owner: "John"
},
screwdriver: {
name: "screwdriver",
number: "72",
owner: "Peter",
},
crowbar: {
name: "crowbar",
number: "6",
owner: "Jack"
}
};
Object.keys(tools).forEach(function(key) {
console.log(key, tools[key].owner); // remove `key,` if you literally want just the owner name logged
});
答案 2 :(得分：0)
您可以使用Array#map收集数组中的名称。
var tools = { hammer: { name: "hammer", number: "23", owner: "John" }, screwdriver: { name: "screwdriver", number: "72", owner: "Peter" }, crowbar: { name: "crowbar", number: "6", owner: "Jack" } },
owners = Object.keys(tools).map(function(key) {
return tools[key].owner;
});
console.log(owners);