DateTimeOffset.DayOfWeek プロパティ

定義

現在の DateTimeOffset オブジェクトによって表される曜日を取得します。Gets the day of the week represented by the current DateTimeOffset object.

public:
 property DayOfWeek DayOfWeek { DayOfWeek get(); };
public DayOfWeek DayOfWeek { get; }
member this.DayOfWeek : DayOfWeek
Public ReadOnly Property DayOfWeek As DayOfWeek

プロパティ値

現在の DateTimeOffset オブジェクトの曜日を示す列挙値の 1 つ。One of the enumeration values that indicates the day of the week of the current DateTimeOffset object.

次の例では、2008年の各月の最初の日の曜日名を表示します。The following example displays the weekday name of the first day of each month of the year 2008.

DateTimeOffset startOfMonth = new DateTimeOffset(2008, 1, 1, 0, 0, 0, 
                                         DateTimeOffset.Now.Offset);
int year = startOfMonth.Year;
do 
{
   Console.WriteLine("{0:MMM d, yyyy} is a {1}.", startOfMonth, startOfMonth.DayOfWeek);
   startOfMonth = startOfMonth.AddMonths(1);
}
while (startOfMonth.Year == year);
// This example writes the following output to the console:
//    Jan 1, 2008 is a Tuesday.
//    Feb 1, 2008 is a Friday.
//    Mar 1, 2008 is a Saturday.
//    Apr 1, 2008 is a Tuesday.
//    May 1, 2008 is a Thursday.
//    Jun 1, 2008 is a Sunday.
//    Jul 1, 2008 is a Tuesday.
//    Aug 1, 2008 is a Friday.
//    Sep 1, 2008 is a Monday.
//    Oct 1, 2008 is a Wednesday.
//    Nov 1, 2008 is a Saturday.
//    Dec 1, 2008 is a Monday.      
Dim startOfMonth As New DateTimeOffset(#1/1/2008#, _
                                      DateTimeOffset.Now.Offset)
Dim year As Integer = startOfMonth.Year
Do While startOfMonth.Year = year
   Console.WriteLine("{0:MMM d, yyyy} is a {1}.", _
                     startOfMonth, startOfMonth.DayOfWeek)
   startOfMonth = startOfMonth.AddMonths(1)                   
Loop      
' This example writes the following output to the console:
'    Jan 1, 2008 is a Tuesday.
'    Feb 1, 2008 is a Friday.
'    Mar 1, 2008 is a Saturday.
'    Apr 1, 2008 is a Tuesday.
'    May 1, 2008 is a Thursday.
'    Jun 1, 2008 is a Sunday.
'    Jul 1, 2008 is a Tuesday.
'    Aug 1, 2008 is a Friday.
'    Sep 1, 2008 is a Monday.
'    Oct 1, 2008 is a Wednesday.
'    Nov 1, 2008 is a Saturday.
'    Dec 1, 2008 is a Monday.      

注釈

DayOfWeek 列挙型の定数の値は、DayOfWeek.Sunday から DayOfWeek.Saturdayまでの範囲です。The value of the constants in the DayOfWeek enumeration ranges from DayOfWeek.Sunday to DayOfWeek.Saturday. 整数にキャストする場合、値は 0 (DayOfWeek.Sundayを示す) から 6 (DayOfWeek.Saturdayを示す) までの範囲内で指定します。If cast to an integer, its value ranges from zero (which indicates DayOfWeek.Sunday) to six (which indicates DayOfWeek.Saturday).

"D" 書式指定子または "dddd" カスタム書式指定子を使用して、特定の日付の曜日名を表示することもできます。You can also display the weekday name of a particular date by using the "D" format specifier or the "dddd" custom format specifier. 次に例を示します。For example:

DateTimeOffset displayDate = new DateTimeOffset(2008, 1, 1, 13, 18, 00, 
                                                DateTimeOffset.Now.Offset);
Console.WriteLine("{0:D}", displayDate);  // Output: Tuesday, January 01, 2008                     
Console.WriteLine("{0:d} is a {0:dddd}.", 
                  displayDate);           // Output: 1/1/2008 is a Tuesday.
Dim displayDate As New DateTimeOffset(#1/1/2008 1:18PM#, _
                                      DateTimeOffset.Now.Offset)
Console.WriteLine("{0:D}", displayDate)    ' Output: Tuesday, January 01, 2008                     
Console.WriteLine("{0:d} is a {0:dddd}.", _
                  displayDate)             ' Output: 1/1/2008 is a Tuesday.

このプロパティによって返される DayOfWeek 列挙メンバーの ToString メソッドを呼び出すことによって返される文字列はローカライズされていないことに注意してください。Note that the string returned by calling the ToString method of the DayOfWeek enumeration member that is returned by this property is not localized. 現在のカルチャまたは特定のカルチャの曜日名を含む文字列を抽出するには、"dddd" カスタム書式指定子を使用して ToString メソッドを呼び出します。To extract a string that contains the weekday name of the current culture or of a specific culture, call the ToString method with the "dddd" custom format specifier. たとえば、次のコードは、fr-fr カルチャを使用して日付の曜日名を表示します。For example, the following code displays the weekday name for a date using the fr-fr culture.

DateTimeOffset thisDate = new DateTimeOffset(2007, 6, 1, 6, 15, 0, 
                                             DateTimeOffset.Now.Offset);
string weekdayName = thisDate.ToString("dddd", 
                                       new CultureInfo("fr-fr")); 
Console.WriteLine(weekdayName);                  // Displays vendredi     
Dim thisDate As New DateTimeOffset(#6/1/2007 6:15AM#, _
                                      DateTimeOffset.Now.Offset)
Dim weekdayName As String = thisDate.ToString("dddd", _
                            New CultureInfo("fr-fr")) 
Console.WriteLine(weekdayName)                        ' Displays vendredi     

適用対象