Question

怎么根据具体的一个日期算出是星期几？

Answer 1

有个公式

以2049年10月1日（100周年国庆）为例，用蔡勒（Zeller）公式进行计算，过程如下：
蔡勒（Zeller）公式：w=y+[y/4]+[c/4]-2c+[26(m+1)/10]+d-1
=49+[49/4]+[20/4]-2×20+[26× (10+1)/10]+1-1
=49+[12.25]+5-40+[28.6]
=49+12+5-40+28
=54 (除以7余5)

即2049年10月1日（100周年国庆）是星期5。

Answer 2

Public Function IsRunnian(ByVal n As Integer) As Boolean
Dim res As Boolean
res = False
If n Mod 400 = 0 Then
res = True
End If
If (n Mod 100 <> 0) And (n Mod 4 = 0) Then
res = True
End If
IsRunnian = res
End Function
Public Function Fc(ByVal td As Date) As Byte
Dim y As Integer
Dim m As Integer
Dim d As Integer
Dim yc As Integer
Dim mc As Integer
Dim dc As Integer
y = Year(td)
m = Month(td)
d = Day(td)

dc = d
If IsRunnian(y) Then
mc = Val(Mid("512503514624", m, 1))
Else
mc = Val(Mid("622503514624", m, 1))
End If
yc = ((y Mod 100) \ 4 + (y Mod 100)) Mod 7

Fc = (yc + mc + dc) Mod 7
End Function

Answer 3

是哪天

Answer 4

你要算哪天？