only first object getting saved in javascript for loop

问题

On parse.com, Im trying to save an object which includes:

• a message body,
• the senders name,
• the senders id,

• and the recipients name

  to a class called "Messages." The object is getting saved correctly, however, when i try to use a for loop in order to save 3 different copies each with a different and random recipient, only the first object gets saved.

randUsers is an array with three random users.

How do i fix this?

function sendLean(leanBody, leanSenderName, leanSenderId, randUsers){
    var Messages = Parse.Object.extend("Messages");
    var messages = new Messages();
    for(var i = 0; i < 3; ++i){

      messages.set("messageBody", leanBody);
      messages.set("recipientId", randUsers[i]);
      messages.set("senderName",  leanSenderName);
      messages.set("senderId", leanSenderId);

      messages.save(null, {
        success: function(messages) {
          // Execute any logic that should take place after the object is saved.
          alert('New object created with objectId: ' + messages.id);
        },
        error: function(messages, error) {
          // Execute any logic that should take place if the save fails.
          // error is a Parse.Error with an error code and message.
          alert('Failed to create new object, with error code: ' + error.message);
        }
      });
    }

回答1:

You need each new instance of your Messages object to be inside your for loop. Change

var messages = new Messages();
for(var i = 0; i < 3; ++i){

to

for(var i=0,l=randUsers.length; i<l; i++){
  var messages = new Messages;

if randUsers is an Array, or

for(var i in randUsers){
  var messages = new Messages;

if randUsers is an Object.

来源：https://stackoverflow.com/questions/26368957/only-first-object-getting-saved-in-javascript-for-loop