ios - 仅从日期时间/日期选择器中快速按日期过滤

Question

我在表单中使用日期时间选择器并将如下数据插入核心数据实体(属性)

   `appointment.date = appointmentDate.date //it is getting date as well and time
    appointment.title = "Appointment"
    do {
        try managedObjectContext.save()`

在另一个 View Controller 中，我这样做是为了根据日期过滤记录。我有一个返回日期的日历。

    let fetchRequest = NSFetchRequest<NSFetchRequestResult>(entityName: "Appointment")
    let sortDescriptor = NSSortDescriptor(key: "date", ascending: true)
    fetchRequest.sortDescriptors = [sortDescriptor]
    let predicate = NSPredicate(format: "date = %@", calendar.selectedDate! as NSDate)
    fetchRequest.predicate = predicate  

尝试仅按日期(忽略时间)进行过滤，但它不起作用(不显示任何内容)。如果我删除谓词，则会显示所有记录。

什么是正确的方法或者我在哪里做错了？是格式问题吗？

Answer 1

如果您想过滤所选天中的记录，您必须应用具有开始和结束日期的谓词

let startDate = Calendar.current.startOfDay(for: calendar.selectedDate)
let endDate = Calendar.current.date(byAdding: .day, value: 1, to: startDate)
let predicate = NSPredicate(format: "date >= %@ AND date < %@", startDate as NSDate, endDate as NSDate)