如何在 Visual Basic 中验证日期是周末

Question

我有一个数组存储来自日期时间选择器的日期，我需要验证是否有任何日期在周末（周六和周日），以便在 BaseRate 之上收取附加费。日期数组用于用 startDate 和 endDate 之间的日期填充数组。这段代码似乎不像我想的那样工作：

Dim dates(Nights) as Date
For i As Integer = 0 To Nights
        dates(i) = StartDay
        StartDay.AddDays(1)
Next

For i As Integer = 0 To Nights
    If dates(i).Day = DayOfWeek.Saturday Or dates(i).Day = DayOfWeek.Sunday Then
        BaseRate += (BaseRate * dclWeekendSurcharge)
    End If
Next

Answer 1

Day 属性是月份中的某天，而不是星期几。使用 Date 对象的 DayOfWeek 属性与 DayOfWeek 枚举进行准确比较。

Dim dates(Nights) as Date
For i As Integer = 0 To Nights
    If dates(i).DayOfWeek = DayOfWeek.Saturday Or dates(i).DayOfWeek = DayOfWeek.Sunday Then
        BaseRate += (BaseRate * dclWeekendSurcharge)
    End If
Next

可以使用以下示例代码将该概念转换为停留时间的费率计算：

Imports System
Imports System.Collections.Generic

Dim nightlyRate as Decimal = 60 '$60/night
Dim weekendSurcharge as Decimal = 0.1 '10% higher
System.Console.WriteLine("$60 = ${0}", GetTotal(Date.Parse("1/1/2015"), Date.Parse("1/2/2015"), nightlyRate, weekendSurcharge))
System.Console.WriteLine("$120 = ${0}", GetTotal(Date.Parse("1/1/2015"), Date.Parse("1/3/2015"), nightlyRate, weekendSurcharge))
System.Console.WriteLine("$186 = ${0}", GetTotal(Date.Parse("1/1/2015"), Date.Parse("1/4/2015"), nightlyRate, weekendSurcharge))

Function GetTotal(startDay as Date, endDay as Date, baseRate as Decimal, weekendSurcharge as Decimal) as Decimal
    Dim total as Decimal = 0
        Do While startDay < endDay
            total += baseRate
            If startDay.DayOfWeek = DayOfWeek.Saturday Or startDay.DayOfWeek = DayOfWeek.Sunday Then
                total += (baseRate * weekendSurcharge) 'Assume surchage is a multiplier, not a dollar rate
            End If
            startDay = startDay.AddDays(1)
        Loop
    Return total
End Function

然后输出：

$60 = $60 '1 night, no weekend
$120 = $120 '2 nights, no weekend
$186 = $186.0 'This is with the 10% multiplier since 1/3 is a weekend