Javascript 获取带有索引的 JS 对象元素
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Get element of JS object with an index
提问by ChapmIndustries
Ok so let's say that I have my object
好吧，让我们说我有我的对象
myobj = {"A":["Abe"], "B":["Bob"]}
and I want to get the first element out of it. As in I want it to return Abewhich has an index of A. How can I do something along the lines of myobj[0]and get out "Abe".
我想从中取出第一个元素。正如我希望它返回Abe索引为A. 我怎么能像myobj[0]“安倍”那样做一些事情。
回答by Reinis
I know it's a late answer, but I think this is what OP asked for.
我知道这是一个迟到的答案，但我认为这就是 OP 要求的。
myobj[Object.keys(myobj)[0]];
回答by Alnitak
JS objects have no defined order, they are (by definition) an unsortedset of key-value pairs.
JS 对象没有定义的顺序，它们（根据定义）是一组未排序的键值对。
If by "first" you mean "first in lexicographical order", you can however use:
如果“第一”是指“按字典顺序排列的第一”，则可以使用：
var sortedKeys = Object.keys(myobj).sort();
and then use:
然后使用：
var first = myobj[sortedKeys[0]];
回答by Dennis Paixao
Object.keys(city)[0]; //return the key name at index 0
Object.values(city)[0] //return the key values at index 0
回答by doset
var myobj = {"A":["Abe"], "B":["Bob"]};
var keysArray = Object.keys(myobj);
var valuesArray = Object.keys(myobj).map(function(k) {
return String(myobj[k]);
});
var mydata = valuesArray[keysArray.indexOf("A")]; // Abe
回答by Fahem Idir
I Hope that will help
我希望这会有所帮助
$.each(myobj, function(index, value) {
console.log(myobj[index]);
)};
回答by Jeffpowrs
myobj.A
------- or ----------
- - - - 或者 - - - - -
myobj['A']
will get you 'B'
会给你'B'
回答by jfriend00
If you want a specific order, then you must use an array, not an object. Objects do not have a defined order.
如果你想要一个特定的顺序，那么你必须使用一个数组，而不是一个对象。对象没有定义的顺序。
For example, using an array, you could do this:
例如，使用数组，您可以这样做：
var myobj = [{"A":["B"]}, {"B": ["C"]}];
var firstItem = myobj[0];
Then, you can use myobj[0] to get the first object in the array.
然后，您可以使用 myobj[0] 获取数组中的第一个对象。
Or, depending upon what you're trying to do:
或者，取决于您要执行的操作：
var myobj = [{key: "A", val:["B"]}, {key: "B", val:["C"]}];
var firstKey = myobj[0].key; // "A"
var firstValue = myobj[0].val; // "["B"]
