C# DateTimeOffset.ParseExact方法代码示例

TextReader conIn = Console.In;
 TextWriter conOut = Console.Out;
 int tries = 0;
 string input = String.Empty;
 string[] formats = new string[] {@"@M/dd/yyyy HH:m zzz", @"MM/dd/yyyy HH:m zzz", 
                                  @"M/d/yyyy HH:m zzz", @"MM/d/yyyy HH:m zzz", 
                                  @"M/dd/yy HH:m zzz", @"MM/dd/yy HH:m zzz", 
                                  @"M/d/yy HH:m zzz", @"MM/d/yy HH:m zzz",                             
                                  @"M/dd/yyyy H:m zzz", @"MM/dd/yyyy H:m zzz", 
                                  @"M/d/yyyy H:m zzz", @"MM/d/yyyy H:m zzz", 
                                  @"M/dd/yy H:m zzz", @"MM/dd/yy H:m zzz", 
                                  @"M/d/yy H:m zzz", @"MM/d/yy H:m zzz",                               
                                  @"M/dd/yyyy HH:mm zzz", @"MM/dd/yyyy HH:mm zzz", 
                                  @"M/d/yyyy HH:mm zzz", @"MM/d/yyyy HH:mm zzz", 
                                  @"M/dd/yy HH:mm zzz", @"MM/dd/yy HH:mm zzz", 
                                  @"M/d/yy HH:mm zzz", @"MM/d/yy HH:mm zzz",                                 
                                  @"M/dd/yyyy H:mm zzz", @"MM/dd/yyyy H:mm zzz", 
                                  @"M/d/yyyy H:mm zzz", @"MM/d/yyyy H:mm zzz", 
                                  @"M/dd/yy H:mm zzz", @"MM/dd/yy H:mm zzz", 
                                  @"M/d/yy H:mm zzz", @"MM/d/yy H:mm zzz"};
 IFormatProvider provider = CultureInfo.InvariantCulture.DateTimeFormat;
 DateTimeOffset result = new DateTimeOffset();

 do { 
    conOut.WriteLine("Enter a date, time, and offset (MM/DD/YYYY HH:MM +/-HH:MM),");
    conOut.Write("Then press Enter: ");
    input = conIn.ReadLine();
    conOut.WriteLine();
    try
    {
       result = DateTimeOffset.ParseExact(input, formats, provider, 
                                          DateTimeStyles.AllowWhiteSpaces);
       break;
    }
    catch (FormatException)
    {
       Console.WriteLine("Unable to parse {0}.", input);      
       tries++;
    }
 } while (tries < 3);
 if (tries >= 3)
    Console.WriteLine("Exiting application without parsing {0}", input);
 else
    Console.WriteLine("{0} was converted to {1}", input, result.ToString());                                                     
 // Some successful sample interactions with the user might appear as follows:
 //    Enter a date, time, and offset (MM/DD/YYYY HH:MM +/-HH:MM),
 //    Then press Enter: 12/08/2007 6:54 -6:00
 //    
 //    12/08/2007 6:54 -6:00 was converted to 12/8/2007 6:54:00 AM -06:00         
 //    
 //    Enter a date, time, and offset (MM/DD/YYYY HH:MM +/-HH:MM),
 //    Then press Enter: 12/8/2007 06:54 -06:00
 //    
 //    12/8/2007 06:54 -06:00 was converted to 12/8/2007 6:54:00 AM -06:00
 //    
 //    Enter a date, time, and offset (MM/DD/YYYY HH:MM +/-HH:MM),
 //    Then press Enter: 12/5/07 6:54 -6:00
 //    
 //    12/5/07 6:54 -6:00 was converted to 12/5/2007 6:54:00 AM -06:00

string dateString, format;  
DateTimeOffset result;
CultureInfo provider = CultureInfo.InvariantCulture;

// Parse date-only value with invariant culture and assume time is UTC.
dateString = "06/15/2008";
format = "d";
try
{
   result = DateTimeOffset.ParseExact(dateString, format, provider, 
                                      DateTimeStyles.AssumeUniversal);
   Console.WriteLine("'{0}' converts to {1}.", dateString, result.ToString());
}
catch (FormatException)
{
   Console.WriteLine("'{0}' is not in the correct format.", dateString);
} 

// Parse date-only value with leading white space.
// Should throw a FormatException because only trailing white space is  
// specified in method call.
dateString = " 06/15/2008";
try
{
   result = DateTimeOffset.ParseExact(dateString, format, provider, 
                                      DateTimeStyles.AllowTrailingWhite);
   Console.WriteLine("'{0}' converts to {1}.", dateString, result.ToString());
}   
catch (FormatException)
{
   Console.WriteLine("'{0}' is not in the correct format.", dateString);
} 

// Parse date and time value, and allow all white space.
dateString = " 06/15/   2008  15:15    -05:00";
format = "MM/dd/yyyy H:mm zzz";
try
{
   result = DateTimeOffset.ParseExact(dateString, format, provider, 
                                      DateTimeStyles.AllowWhiteSpaces);
   Console.WriteLine("'{0}' converts to {1}.", dateString, result.ToString());
}   
catch (FormatException)
{
   Console.WriteLine("'{0}' is not in the correct format.", dateString);
} 

// Parse date and time and convert to UTC.
dateString = "  06/15/2008 15:15:30 -05:00";
format = "MM/dd/yyyy H:mm:ss zzz"; 
try
{
   result = DateTimeOffset.ParseExact(dateString, format, provider, 
                                      DateTimeStyles.AllowWhiteSpaces |
                                      DateTimeStyles.AdjustToUniversal);
   Console.WriteLine("'{0}' converts to {1}.", dateString, result.ToString());
}
catch (FormatException)
{
   Console.WriteLine("'{0}' is not in the correct format.", dateString);
}

//引入命名空间
using System;
using System.Globalization;

public class Example
{
   public static void Main()
   {
      string[] dateStrings = { "2018-08-18T12:45:16.0000000Z",
                               "2018/08/18T12:45:16.0000000Z",
                               "2018-18-08T12:45:16.0000000Z",
                               "2018-08-18T12:45:16.0000000",                               
                               " 2018-08-18T12:45:16.0000000Z ",
                               "2018-08-18T12:45:16.0000000+02:00",
                               "2018-08-18T12:45:16.0000000-07:00" }; 
      
      ParseWithISO8601(dateStrings, DateTimeStyles.None);
      Console.WriteLine("\n-----\n");
      ParseWithISO8601(dateStrings, DateTimeStyles.AllowWhiteSpaces);
      Console.WriteLine("\n-----\n");
      ParseWithISO8601(dateStrings, DateTimeStyles.AdjustToUniversal);
      Console.WriteLine("\n-----\n");
      ParseWithISO8601(dateStrings, DateTimeStyles.AssumeLocal);
      Console.WriteLine("\n-----\n");
      ParseWithISO8601(dateStrings, DateTimeStyles.AssumeUniversal);   }

   private static void ParseWithISO8601(string[] dateStrings, DateTimeStyles styles)
   {   
      Console.WriteLine($"Parsing with {styles}:");
      foreach (var dateString in dateStrings)
      {
         try {
            var date = DateTimeOffset.ParseExact(dateString, "O", null, styles);
            Console.WriteLine($"   {dateString,-35} --> {date:yyyy-MM-dd HH:mm:ss.FF zzz}");
         }
         catch (FormatException)
         {
            Console.WriteLine($"   FormatException: Unable to convert '{dateString}'");
         }   
      } 
   }
}

string dateString, format;  
DateTimeOffset result;
CultureInfo provider = CultureInfo.InvariantCulture;

// Parse date-only value with invariant culture.
dateString = "06/15/2008";
format = "d";
try
{
   result = DateTimeOffset.ParseExact(dateString, format, provider);
   Console.WriteLine("{0} converts to {1}.", dateString, result.ToString());
}   
catch (FormatException)
{
   Console.WriteLine("{0} is not in the correct format.", dateString);
} 

// Parse date-only value without leading zero in month using "d" format.
// Should throw a FormatException because standard short date pattern of 
// invariant culture requires two-digit month.
dateString = "6/15/2008";
try
{
   result = DateTimeOffset.ParseExact(dateString, format, provider);
   Console.WriteLine("{0} converts to {1}.", dateString, result.ToString());
}
catch (FormatException)
{
   Console.WriteLine("{0} is not in the correct format.", dateString);
} 

// Parse date and time with custom specifier.
dateString = "Sun 15 Jun 2008 8:30 AM -06:00";
format = "ddd dd MMM yyyy h:mm tt zzz";
try
{
   result = DateTimeOffset.ParseExact(dateString, format, provider);
   Console.WriteLine("{0} converts to {1}.", dateString, result.ToString());
}
catch (FormatException)
{
   Console.WriteLine("{0} is not in the correct format.", dateString);
} 

// Parse date and time with offset without offset//s minutes.
// Should throw a FormatException because "zzz" specifier requires leading  
// zero in hours.
dateString = "Sun 15 Jun 2008 8:30 AM -06";
try
{
   result = DateTimeOffset.ParseExact(dateString, format, provider);
   Console.WriteLine("{0} converts to {1}.", dateString, result.ToString());
}
catch (FormatException)
{
   Console.WriteLine("{0} is not in the correct format.", dateString);
}

//引入命名空间
using System;

public class Example
{
   public static void Main()
   {
      string[] dateStrings = { "2018-08-18T12:45:16.0000000Z",
                               "2018/08/18T12:45:16.0000000Z",
                               "2018-18-08T12:45:16.0000000Z",
                               " 2018-08-18T12:45:16.0000000Z ",
                               "2018-08-18T12:45:16.0000000+02:00",
                               "2018-08-18T12:45:16.0000000-07:00" }; 
      
      foreach (var dateString in dateStrings)
      {
         try {
            var date = DateTimeOffset.ParseExact(dateString, "O", null);
            Console.WriteLine($"{dateString,-35} --> {date:yyyy-MM-dd HH:mm:ss.FF zzz}");
         }
         catch (FormatException)
         {
            Console.WriteLine($"FormatException: Unable to convert '{dateString}'");
         }   
      } 
   }
}