以数字格式获取当前日期的最有效方法？

Question

我有这段代码可以获取当前日期（例如星期一、星期二）并将其转换为数字格式，以 saturday = 1、monday = 2 等开头

    Dim Current_Day As String = Format(Now, "dddd")
    Dim Day_Name_Val As String = "0"

    Select Case Current_Day
        Case "Saturday"
            Day_Name_Val = "1"
        Case "Monday"
            Day_Name_Val = "2"
        Case "Tuesday"
            Day_Name_Val = "3"
        Case "Wednesday"
            Day_Name_Val = "4"
        Case "Thursday"
            Day_Name_Val = "5"
        Case "Friday"
            Day_Name_Val = "6"
        Case "Sunday"
            Day_Name_Val = "7"
    End Select

是否有有效或更好的方法来做到这一点？也许是 vb.net?

的内置函数

Answer 1

您可以使用

int dayInNumber = (int)Now.DayOfWeek

以数字形式获取当前日期。如果是星期天，你可能想做类似

的事情

 if(dayInNumber == 0){ dayInNumber = 7;}

因为枚举是从0开始的

代码采用 C# 语法，但您可以将其转换为 vb.net

中的等效语法

Answer 2

对于这种情况，您可以使用 DayOfWeek 枚举。

  Dim dayNumber As Integer = Now.DayOfWeek()

Answer 3

因为 DayOfWeek 的默认值是：

Enum DayOfWeek 
    Sunday = 0
    Monday = 1
    Tuesday = 2
    Wednesday = 3
    Thursday = 4
    Friday = 5
    Saturday = 6
End Enum

我会定义你自己的：

Enum MyDayOfWeek 
    Saturday = 1
    Monday = 2
    Tuesday = 3
    Wednesday = 4
    Thursday = 5
    Friday = 6
    Sunday = 7
End Enum

这样你就可以做类似的事情：

Dim Day_Name_Val = Convert.ToInt32([Enum].Parse(GetType(MyDayOfWeek),
    DateTime.Now.DayOfWeek.ToString()))

Fiddle Demo

以数字格式获取当前日期的最有效方法？

Most efficient way to get the current day in number format?

vb.net

performance

dayofweek