獲取數組鍵的名稱

Question

我有一個像這樣的JSON：

{
        "myName":{
                 "forename":"alf",
                 "surname":"cool",
                 "phone":"000000000000",
                 "email":"mail@com"
},.....

我可以訪問每個鍵的代碼

 for (var key in contacts) {
                          if (contacts.hasOwnProperty(key)) {
                                var newRow = new Element('li');
                                newRow.addClass('contact');
                                newRow.set('html', contacts[key].forename + ' ' + contacts[key].surname);

                                var innerSpan = new Element('span').set('html', contacts[key].phone + ', ' + contacts[key].email);
                                innerSpan.addClass('details');
                                innerSpan.set('html', contacts[key].phone + ', ' + contacts[key].email);
                                innerSpan.inject(newRow);

                                newRow.addEvent("click", this.setFromContact.bind(this, contacts[key]));
                                newRow.inject($(this.list));
                               // save myName to a variale here!!

                          }
                 }

現在，我想將“ myName”保存到變量中。

Answer 1

另外，MooTools和ES5提供了Object.keys

var obj = {
    myName: { }
    yourName: { }
};

console.log(Object.keys(obj)); // ['myName', 'yourName']; 

我還建議您將Object.each(obj, fn(value, key, obj){})用於迭代器。 參見http://mootools.net/core/docs/1.5.1/Types/Object#Object:Object-each

它給您一個閉包，這樣就不會重新聲明變量並且不會互相干擾。

var keys = [];
Object.each(contacts, function(value, key){
    var newRow = new Element('li.contact').set('html', '{forename} {surname}'.substitute(value)),
        innerSpan = new Element('span.details').set('html', '{phone}, {email}'.substitute(value)).inject(newRow);

    newRow.addEvent("click", this.setFromContact.bind(this, value)).inject($(this.list));
    keys.push(key); // avoids extra Object.keys call
}, this);

Answer 2

您可以測試鍵的值，如果值是“ myName”，則可以將其保存到變量中。

var myName = '';
for (var key in contacts) {
    if(key == "myName")
        myName = key;
}

Answer 3

// Variable with the "myName" object    
var myVariable = contacts[key];

鍵變量是一個字符串，例如“ myName”