使用空指针列解析保存对象

Question

是否可以使用空列（指针值）保存解析对象？

在我的代码中，如果用户未登录，我想将“userSubmitted”留空

        var sendReport = PFObject(className:"UserReport")
        sendReport["ReportReason"] = reason
        sendReport["ReportedPhoto"] = reportedPhoto
        if PFUser.currentUser() == nil
        {
            sendReport["UserSubmitted"] = nil
            //sendReport["UserSubmitted"] = ""
        } else {
            sendReport["UserSubmitted"] = PFUser.currentUser()
        }
        sendReport.saveInBackgroundWithBlock {
        [...]
        }

在sendReport["UserSubmitted"] = nil和sendReport["UserSubmitted"] = ""

处崩溃

[Error]: invalid type for key UserSubmitted, expected *_User, but got string (Code: 111, Version: 1.7.2)

Answer 1

要取消设置属性，请使用removeObjectForKey ...

sendReport.removeObjectForKey("UserSubmitted")