Get information about the world's time zones and daylight savings Net2.0 under.

Under. NET 3.5, there is a timezoneinfo class that makes it easy to transform time zones and time transitions. However, under. NET 2.0, it is inconvenient to only handle the current server time zone. Special systems are used worldwide and need to be considered for local time zones, especially daylight saving times. Otherwise, time will go wrong. How to solve this problem, it is necessary to manually handle the.

In fact, Windows time zone information is stored in the Windows Registry "SOFTWARE\Microsoft\Windows NT\CurrentVersion\Time Zones" Just read the relevant information. You can achieve the same function as TimeZoneInfo. Below we will be through a small demo. Reads the world time zone information, calculates the time zone offset and the daylight saving time offset. and determines whether the time is in the daylight savings period of the timezone according to the user's selected timezone and input times.

First, we need to create two struct to record the relevant information, one is Sytemtime, one timezoneinformation. The code is as follows:

 [StructLayout (layoutkind.sequential)] 


 struct SYSTEMTIME 


     { 


 public ushort Wyear; 


 public ushort Wmonth; 


 public ushort Wdayofweek; 


 public ushort Wday; 


 public ushort Whour; 


 public ushort Wminute; 


 public ushort Wsecond; 


 public ushort Wmilliseconds;


 public void SetInfo (byte[] info) 


         { 


 if (info. Length!= marshal.sizeof (this)) 


             { 


 throw new ArgumentException ("Information size is incorrect", "info"); 


             } 


 Else 


             { 


 this.wyear = bitconverter.touint16 (info, 0); 


 This.wmonth = bitconverter.touint16 (info, 2); 


 This.wdayofweek = bitconverter.touint16 (info, 4); 


 This.wday = bitconverter.touint16 (info, 6); 


 This.whour = bitconverter.touint16 (info, 8); 


 This.wminute = bitconverter.touint16 (info, 10); 


 This.wsecond = bitconverter.touint16 (info, 12); 


 this.wmilliseconds = bitconverter.touint16 (info, 14);


             } 


         } 


 public override bool Equals (object obj) 


         { 


 if (this. GetType () = = obj. GetType ()) 


             { 


 Try 


                 { 


 SYSTEMTIME objst = (SYSTEMTIME) obj; 


 if (this.wyear!= objst.wyear 


                         || This.wmonth!= Objst.wmonth 


                         || This.wdayofweek!= Objst.wdayofweek 


                         || This.wday!= Objst.wday 


                         || This.whour!= Objst.whour 


                         || This.wminute!= Objst.wminute 


                         || This.wsecond!= Objst.wsecond 


                         || This.wmilliseconds!= objst.wmilliseconds) 


 return false;


 Else 


 return true; 


                 } 


 Catch 


                 { 


 return false; 


                 } 


             } 


 Else 


 return false; 


         } 


 public override int GetHashCode () 


         { 


 return base. GetHashCode (); 


         } 


     }