Date Formatter 和 ParseException - 从 Java 迁移到 C#
本文关键字：Java 迁移 Formatter ParseException Date | 更新日期: 2023-09-27 18:33:50
这是我的C#类的更新版本，我收到消息：
检测到无法访问的代码：DateTime.Now.Ticks;
其他一切似乎都还可以。我的错误在哪里？
using System;
using System.Globalization;
namespace domain
{
public class Request : Unique
{
private DateTime dateBooked_Renamed;
private DateTime dateSignedIn ;
private DateTime dateSignedOut ;
private bool arrived_Renamed = false;
private bool paid_Renamed = false;
private Hotel hotel_Renamed;
private Employee employee_Renamed;
private int numberOfNights;
public Request(Hotel hotel, Employee employee, string dateBooked, string dateArrived, int numberOfNights)
: base()
{
this.hotel_Renamed = hotel;
this.employee_Renamed = employee;
this.numberOfNights = numberOfNights;
try
{
DateTime.ParseExact(dateBooked, "dd/MM/yyyy", CultureInfo.InvariantCulture);
this.dateBooked_Renamed = DateTime.ParseExact(dateBooked, "dd/MM/yyyy", CultureInfo.InvariantCulture);
this.dateSignedIn = DateTime.ParseExact(dateArrived, "dd/MM/yyyy", CultureInfo.InvariantCulture);
}
catch (FormatException e)
{
Console.WriteLine(e.ToString());
Console.Write(e.StackTrace);
}
}
public virtual bool checkout(double money, string date)
{
try
{
dateCheckedOut = DateTime.ParseExact(date, "dd/MM/yyyy", CultureInfo.InvariantCulture);
}
catch (FormatException e)
{
Console.WriteLine(e.ToString());
Console.Write(e.StackTrace);
}
if (money >= price())
{
paid = true;
}
else
{
paid = false;
}
return paid_Renamed;
}
public virtual int days()
{
long tNow = dateSignedOut != null ? dateSignedOut.Ticks : DateTime.Now.Ticks;
long tThen = arrived ? dateArrived.Ticks : tNow;
long diff = tNow - tThen;
long secondInMillis = 1000;
long minuteInMillis = secondInMillis * 60;
long hourInMillis = minuteInMillis * 60;
long dayInMillis = hourInMillis * 24;
long yearInMillis = dayInMillis * 365;
diff = diff % yearInMillis;
long elapsedDays = diff / dayInMillis;
return (int)elapsedDays;
}
public virtual Hotel hotel
{
get
{
return hotel_Renamed;
}
set
{
this.hotel_Renamed = value;
}
}
public virtual DateTime dateArrived
{
get
{
return dateSignedIn;
}
set
{
this.dateSignedIn = value;
}
}
public virtual DateTime dateBooked
{
get
{
return dateBooked_Renamed;
}
set
{
this.dateBooked_Renamed = value;
}
}
public virtual DateTime dateCheckedOut
{
get
{
return dateSignedOut;
}
set
{
this.dateSignedOut = value;
}
}
public virtual Employee employee
{
get
{
return employee_Renamed;
}
set
{
this.employee_Renamed = value;
}
}
public virtual bool arrived
{
get
{
return arrived_Renamed;
}
set
{
this.arrived_Renamed = value;
}
}
public virtual bool paid
{
get
{
return paid_Renamed;
}
set
{
this.paid_Renamed = value;
}
}
public virtual double price()
{
// The total cost of the stay...
double price = days() * employee_Renamed.type.price;
if (hotel_Renamed.premium)
{
return price - (0.2 * price);
}
else
{
return price;
}
}
public virtual bool hasArrivalDate(string date)
{
try
{
DateTime d = DateTime.ParseExact(date, "dd/MM/yyyy", CultureInfo.InvariantCulture);
Console.WriteLine("Comparing " + d + " with " + dateSignedIn + " = " + dateSignedIn.ToString("dd/MM/yyyy").Equals(d.ToString("dd/MM/yyyy")));
return dateSignedIn.ToString().Equals(d.ToString());
}
catch (FormatException e)
{
Console.WriteLine(e.ToString());
Console.Write(e.StackTrace);
return false;
}
}
}
}
如果您的日期字符串采用标准格式，则可以使用 DateTime.Parse(date)
如果没有，您可以使用DateTime.ParseExact(date,"your custom format",CultureInfo.InvariantCulture)
作为代码中的示例
public virtual bool hasArrivalDate(string date)
{
try
{
DateTime d = DateTime.ParseExact(date,"dd/MM/yyyy",CultureInfo.InvariantCulture);
Console.WriteLine("Comparing " + d.ToString("dd/MM/yyyy") + " with " + dateSignedIn.ToString("dd/MM/yyyy") + " = " + dateSignedIn.ToString("dd/MM/yyyy").Equals(d.ToString("dd/MM/yyyy")));
return dateSignedIn.ToString().Equals(d.ToString());
}
catch (FormatException e)
{
Console.WriteLine(e.ToString());
Console.Write(e.StackTrace);
return false;
}
}
所以，它不需要日期格式的实例
在您的代码中，dateSignedOut 变量是一个 DateTime ，它永远不能为空。
因此，在这一行中：
long tNow = dateSignedOut != null ? dateSignedOut.Ticks : DateTime.Now.Ticks;
dateSignedOut 永远不会为空，因此永远不会到达语句的"else"部分。
如果希望 dateSignedOut 可为空，请将其设为Nullable<DateTime>（或DateTime?）。
顺便说一句，请格式化您的问题，使其更具可读性。 这个确实有被关闭的危险。 更好的问题会带来更好的答案。
根据评论进行更新
您可能应该尝试更多地了解属性通常如何用 C# 编写，但这超出了本问题的范围。 要使用已有的代码，请执行以下操作：
private DateTime? dateSignedOut; // Notice the ? to make it Nullable
long tNow = dateSignedOut.HasValue ? dateSignedOut.Ticks : DateTime.Now.Ticks;
看看一些MSDN文档，或Google Nullable类型。