日期之间的季度计数

Question

我想计算给定时间跨度内总季度(一年)的计数.

例如:

start date = 1-june -2009
end date = 18-july-2011

count should be = 10.

one more 
start date = 4-Jan-2009 
end date = 27-oct -2010
count =8.

我无法得到正确的结果.

Answer 1

你的例子是错的:4-Jan-2009和之间只有7个季度27-oct -2010

您只需添加Microsoft.VisualBasic.dll对项目的引用并使用DateDiff:

VB:

Public Shared Function getQuartersBetween(ByVal d1 As Date, ByVal d2 As Date) As Int32
    Return DateDiff(DateInterval.Quarter, d1, d2)
End Function

C#:

public static int getQuartersBetween(System.DateTime d1, System.DateTime d2)
{
    return Microsoft.VisualBasic.DateAndTime.DateDiff(DateInterval.Quarter, d1, d2);
}

或者您可以编写自己的实现:

public class Quarter
{

    public static long GetQuarters(DateTime dt1, DateTime dt2) 
    { 
        double d1Quarter = GetQuarter(dt1.Month); 
        double d2Quarter = GetQuarter(dt2.Month); 
        double d1 = d2Quarter - d1Quarter; 
        double d2 = (4 * (dt2.Year - dt1.Year)); 
        return Round(d1 + d2); 
    } 

    private static int GetQuarter(int nMonth) 
    { 
        if (nMonth <= 3) 
            return 1; 
        if (nMonth <= 6) 
            return 2; 
        if (nMonth <= 9) 
            return 3; 
        return 4; 
    } 

    private static long Round(double dVal) 
    { 
        if (dVal >= 0) 
              return (long)Math.Floor(dVal); 
        return (long)Math.Ceiling(dVal); 
    } 
}

或者在VB.NET中:

Public Class Quarter

    Public Shared Function GetQuarters(ByVal dt1 As DateTime, ByVal dt2 As DateTime) As Long
        Dim d1Quarter As Double = GetQuarter(dt1.Month)
        Dim d2Quarter As Double = GetQuarter(dt2.Month)
        Dim d1 As Double = d2Quarter - d1Quarter
        Dim d2 As Double = (4 * (dt2.Year - dt1.Year))
        Return Round(d1 + d2)
    End Function

    Private Shared Function GetQuarter(ByVal nMonth As Integer) As Integer
        If nMonth <= 3 Then
            Return 1
        End If
        If nMonth <= 6 Then
            Return 2
        End If
        If nMonth <= 9 Then
            Return 3
        End If
        Return 4
    End Function

    Private Shared Function Round(ByVal dVal As Double) As Long
        If dVal >= 0 Then
            Return CLng(Math.Floor(dVal))
        End If
        Return CLng(Math.Ceiling(dVal))
    End Function

End Class