无法从 Parse 对象中检索 createdAt 值 [英] Unable to retrieve createdAt values from Parse objects

问题描述

我无法从 Parse 获取每个对象的 createdAt 值.而且我不想在数据就在那里时将额外的时间戳保存为字符串.

这是我正在做的事情的清单.我希望有人可以提供帮助----------------------------------------------------------------------

 var followArray = [String]()var resultsNameArray = [String]()var resultsIcon = [PFFile]()var resultsImgArray = [PFFile?]()var resultsTimeTampArray = [NSDate?]()-------------------------------------------------------------------函数刷新结果(){var followQuery = PFQuery(className: "Follow")followQuery.whereKey("user", equalTo: PFUser.currentUser()!.username!)followQuery.findObjectsInBackgroundWithBlock { (objects: [AnyObject]?, error: NSError?) ->作废如果错误 == 零{对于对象中的对象！{ self.followArray.append(object.objectForKey("Following") as!String)}var query = PFQuery(className: "Moments")query.whereKey("userName", containsIn: self.followArray)query.addDescendingOrder("createdAt")query.findObjectsInBackgroundWithBlock { (objects: [AnyObject]?, error: NSError?) ->作废如果错误 == 零{对于对象中的对象！{self.resultsNameArray.append(object.objectForKey("profileName") as!String)self.resultsIcon.append(object.objectForKey("icon") as!PFFile)self.resultsImgArray.append(object.objectForKey("image") as?PFFile)//尝试使用createdAt"属性，但我仍然从 Parse 获取 nil 值self.resultsTimeTampArray.append(object.objectForKey("createdAt") as! NSDate)}//重新加载表self.resultsTable.reloadData()}}}}-----------------------------------------------------------------------func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) ->UITableViewCell{var cell:TimelineCell = tableView.dequeueReusableCellWithIdentifier("Cell") as!时间线单元格在此处输入代码//我在这里遇到错误！//致命错误:在展开可选值时意外发现 nil//数据格式化程序var dateFormatter:NSDateFormatter = NSDateFormatter()dateFormatter.dateFormat = "yyyy-MM-dd"var strDate = dateFormatter.stringFromDate(self.resultsTimeTampArray[indexPath.row]!)返回单元格}

解决方案

不要使用 objectForKey 访问它，直接通过 createdAt 属性访问它.

正如文档中明确指出的，密钥:

<块引用>

这不包括 createdAt、updatedAt、authData 或 objectId.它确实包括用户名和 ACL 等内容.

I cannot get the createdAt value from Parse for each object.And I dont want to have to save an additional timestamp as a String when the data is sitting right there.

This is the list of what i was doing.I hope someone who can help ----------------------------------------------------------------------

 var followArray = [String]()
        var resultsNameArray = [String]()
        var resultsIcon = [PFFile]()
        var resultsImgArray = [PFFile?]()
        var resultsTimeTampArray = [NSDate?]()

    -------------------------------------------------------------------






     func refreshResult()
            {

            var followQuery = PFQuery(className: "Follow") 
   followQuery.whereKey("user", equalTo: PFUser.currentUser()!.username!) 
 followQuery.findObjectsInBackgroundWithBlock { (objects: [AnyObject]?, error: NSError?) -> Void in
                    if error == nil
                    {
                        for object in objects!
                        {                      self.followArray.append(object.objectForKey("Following") as! String)                    
                        }

                        var query = PFQuery(className: "Moments")
                        query.whereKey("userName", containedIn: self.followArray)

                        query.addDescendingOrder("createdAt")
                        query.findObjectsInBackgroundWithBlock { (objects: [AnyObject]?, error: NSError?) -> Void in

                            if error == nil
                            {
                                for object in objects!
                                { 
                               self.resultsNameArray.append(object.objectForKey("profileName") as! String)
                                self.resultsIcon.append(object.objectForKey("icon") as! PFFile) 
                          self.resultsImgArray.append(object.objectForKey("image") as? PFFile) 

        //tried to use  "createdAt" property  but it i still getting nil value from Parse  
                       self.resultsTimeTampArray.append(object.objectForKey("createdAt") as! NSDate)
                                }
        //reload table
         self.resultsTable.reloadData()
                            }
                        }
                    }
                }

        -----------------------------------------------------------------------
            func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell
            {        
                var cell:TimelineCell = tableView.dequeueReusableCellWithIdentifier("Cell") as! TimelineCell

               enter code here //I'v got an error here!
                //fatal error: unexpectedly found nil while unwrapping an Optional value
    // dataFormatter
                var dateFormatter:NSDateFormatter = NSDateFormatter()
                dateFormatter.dateFormat = "yyyy-MM-dd"
                var strDate = dateFormatter.stringFromDate(self.resultsTimeTampArray[indexPath.row]!)       
                return cell
            }

解决方案

Don't access it using objectForKey, just access it directly via the createdAt property.

As explicitly stated in the docs, the keys:

This does not include createdAt, updatedAt, authData, or objectId. It does include things like username and ACL.

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