Question

当太阳将在某一天设定并上升时，在C＃中有一种方法可以计算纬度和经度吗？

Answer 1

Javascript计算 ~~here~~ 。现在你只需要移植。

编辑：现在计算在this page的源代码中。

编辑：here是源代码的直接链接。无需通过html进行搜索。

Answer 2

我使用NAA javascript和c＃在C＃中创建这个库。

Sunrise and Sunset in C#

我对这两个网站进行了测试，它显示的时间与网站完全相同。

http://www.timeanddate.com/sun/usa/seattle

http://www.esrl.noaa.gov/gmd/grad/solcalc/

Answer 3

这个API似乎对我有用：

http://sunrise-sunset.org/api

Answer 4

接受的答案是JavaScript实现，它不适合我的应用程序，因为我需要在C＃中进行计算。

我已经使用了这个C＃代码：http://wiki.crowe.co.nz/Calculate%20Sunrise%2fSunset.ashx，我已经在这里验证了日出/日落时间：http://www.timeanddate.com/astronomy/。

如果我将秒数舍入到最接近的分钟，则C＃实施的日出和日落时间与timeanddate.com上显示的相应值相匹配，包括夏令时。虽然代码有点压倒性（除非你也喜欢月相数据），所以我会重构它以便具体完成我现在要求的数字是正确的。

Answer 5

我知道这篇文章很老了，但万一有人还在看......

CoordinateSharp可作为Nuget包使用。它是一个独立的包装，可以处理太阳和月亮时间。

Celestial cel = Celestial.CalculateCelestialTimes(85.57682, -70.75678, new DateTime(2017,8,21));
Console.WriteLine(cel.SunRise.Value.ToString());

注意：

假设DateTimes始终为UTC。

最后，如果日期返回null，您可能需要引用太阳/月亮.Condition天体。当太阳全天上升/下降时会发生这种情况。

编辑1/9/2019

自此帖以来，图书馆发生了巨大变化。它现在也可以处理当地时间。

Answer 6

从这个信息开始：

Sunrise_equation

我正在使用它来编写一个仍在制作中的ruby脚本。我无法理解多部分朱利安日期。

有一点很清楚，那就是你应该去寻找精确的太阳运输时间。然后减去并添加基于的semi_diurnal_arc = acos（cos_omega）根据你的纬度和太阳赤纬。哦!并确保包括太阳能中心和地球折射。看来这个地球真的是魔术师。

Answer 7

我已经制作了一个快速的Python脚本：SunriseSunsetCalculator

我还没有将它包装在一个类中，但它可能对其他人有用。

编辑：开源很棒，因为提交基本脚本，有人将其包装在模块中，另一个添加了一个cli界面！感谢mbideau和nfischer的贡献！

Answer 8

dot.答案的VB.Net版本，它也可以自动确定时区。

输出（通过观看今晚的日落来检查）：

Main.VB：

Module Main

Sub Main()

    ' http://www.timeanddate.com/sun/usa/seattle
    ' http://www.esrl.noaa.gov/gmd/grad/solcalc/

    ' Vessy, Switzerland
    Dim latitude As Double = 46.17062
    Dim longitude As Double = 6.161667
    Dim dst As Boolean = True
    Dim timehere As DateTime = DateTime.Now

    Console.WriteLine("It is currently {0:HH:mm:ss} UTC", DateTime.UtcNow)
    Console.WriteLine("The time here, at {0}°,{1}° is {2:HH:mm:ss}", latitude, longitude, timehere)
    Dim local As TimeZoneInfo = TimeZoneInfo.Local
    Dim zone As Integer = local.BaseUtcOffset().TotalHours

    If local.SupportsDaylightSavingTime Then
        Dim standard As String = local.StandardName
        Dim daylight As String = local.DaylightName
        dst = local.IsDaylightSavingTime(timehere)
        Dim current As String = IIf(dst, daylight, standard)
        Console.WriteLine("Daylight-saving time is supported here. Current offset {0:+0} hours, {1}", zone, current)
    Else
        Console.WriteLine("Daylight-saving time is not supported here")
    End If

    System.Console.WriteLine("Sunrise today {0}", Sunrises(latitude, longitude))
    System.Console.WriteLine("Sunset  today {0}", Sunsets(latitude, longitude))
    System.Console.ReadLine()
End Sub

End Module

Sun.vb：

Public Module Sun
' Get sunrise time at latitude, longitude using local system timezone
Function Sunrises(latitude As Double, longitude As Double) As DateTime
    Dim julian As Double = JulianDay(DateTime.Now)
    Dim rises As Double = SunRiseUTC(julian, latitude, longitude)
    Dim timehere As DateTime = DateTime.Now
    Dim local As TimeZoneInfo = TimeZoneInfo.Local
    Dim dst As Boolean = local.IsDaylightSavingTime(timehere)
    Dim zone As Integer = local.BaseUtcOffset().TotalHours
    Dim result As DateTime = getDateTime(rises, zone, timehere, dst)
    Return result
End Function
' Get sunset time at latitude, longitude using local system timezone
Function Sunsets(latitude As Double, longitude As Double) As DateTime
    Dim julian As Double = JulianDay(DateTime.Now)
    Dim rises As Double = SunSetUTC(julian, latitude, longitude)
    Dim timehere As DateTime = DateTime.Now
    Dim local As TimeZoneInfo = TimeZoneInfo.Local
    Dim dst As Boolean = local.IsDaylightSavingTime(timehere)
    Dim zone As Integer = local.BaseUtcOffset().TotalHours
    Dim result As DateTime = getDateTime(rises, zone, timehere, dst)
    Return result
End Function
' Convert radian angle to degrees
Public Function Degrees(angleRad As Double) As Double
    Return (180.0 * angleRad / Math.PI)
End Function
' Convert degree angle to radians
Public Function Radians(angleDeg As Double) As Double
    Return (Math.PI * angleDeg / 180.0)
End Function
'* Name: JulianDay  
'* Type: Function   
'* Purpose: Julian day from calendar day    
'* Arguments:   
'* year : 4 digit year  
'* month: January = 1   
'* day : 1 - 31 
'* Return value:    
'* The Julian day corresponding to the date 
'* Note:    
'* Number is returned for start of day. Fractional days should be   
'* added later. 
Public Function JulianDay(year As Integer, month As Integer, day As Integer) As Double
    If month <= 2 Then
        year -= 1
        month += 12
    End If
    Dim A As Double = Math.Floor(year / 100.0)
    Dim B As Double = 2 - A + Math.Floor(A / 4)

    Dim julian As Double = Math.Floor(365.25 * (year + 4716)) + Math.Floor(30.6001 * (month + 1)) + day + B - 1524.5
    Return julian
End Function

Public Function JulianDay([date] As DateTime) As Double
    Return JulianDay([date].Year, [date].Month, [date].Day)
End Function

'***********************************************************************/
'* Name: JulianCenturies    
'* Type: Function   
'* Purpose: convert Julian Day to centuries since J2000.0.  
'* Arguments:   
'* julian : the Julian Day to convert   
'* Return value:    
'* the T value corresponding to the Julian Day  
'***********************************************************************/

Public Function JulianCenturies(julian As Double) As Double
    Dim T As Double = (julian - 2451545.0) / 36525.0
    Return T
End Function


'***********************************************************************/
'* Name: JulianDayFromJulianCentury 
'* Type: Function   
'* Purpose: convert centuries since J2000.0 to Julian Day.  
'* Arguments:   
'* t : number of Julian centuries since J2000.0 
'* Return value:    
'* the Julian Day corresponding to the t value  
'***********************************************************************/

Public Function JulianDayFromJulianCentury(t As Double) As Double
    Dim julian As Double = t * 36525.0 + 2451545.0
    Return julian
End Function


'***********************************************************************/
'* Name: calGeomMeanLongSun 
'* Type: Function   
'* Purpose: calculate the Geometric Mean Longitude of the Sun   
'* Arguments:   
'* t : number of Julian centuries since J2000.0 
'* Return value:    
'* the Geometric Mean Longitude of the Sun in degrees   
'***********************************************************************/

Public Function GemoetricMeanLongitude(t As Double) As Double
    Dim L0 As Double = 280.46646 + t * (36000.76983 + 0.0003032 * t)
    While L0 > 360.0
        L0 -= 360.0
    End While
    While L0 < 0.0
        L0 += 360.0
    End While
    Return L0
    ' in degrees
End Function


'***********************************************************************/
'* Name: calGeomAnomalySun  
'* Type: Function   
'* Purpose: calculate the Geometric Mean Anomaly of the Sun 
'* Arguments:   
'* t : number of Julian centuries since J2000.0 
'* Return value:    
'* the Geometric Mean Anomaly of the Sun in degrees 
'***********************************************************************/

Public Function GemoetricMeanAnomaly(t As Double) As Double
    Dim M As Double = 357.52911 + t * (35999.05029 - 0.0001537 * t)
    Return M
    ' in degrees
End Function

'***********************************************************************/
'* Name: EarthOrbitEccentricity 
'* Type: Function   
'* Purpose: calculate the eccentricity of earth's orbit 
'* Arguments:   
'* t : number of Julian centuries since J2000.0 
'* Return value:    
'* the unitless eccentricity    
'***********************************************************************/


Public Function EarthOrbitEccentricity(t As Double) As Double
    Dim e As Double = 0.016708634 - t * (0.000042037 + 0.0000001267 * t)
    Return e
    ' unitless
End Function

'***********************************************************************/
'* Name: SunCentre  
'* Type: Function   
'* Purpose: calculate the equation of center for the sun    
'* Arguments:   
'* t : number of Julian centuries since J2000.0 
'* Return value:    
'* in degrees   
'***********************************************************************/


Public Function SunCentre(t As Double) As Double
    Dim m As Double = GemoetricMeanAnomaly(t)

    Dim mrad As Double = Radians(m)
    Dim sinm As Double = Math.Sin(mrad)
    Dim sin2m As Double = Math.Sin(mrad + mrad)
    Dim sin3m As Double = Math.Sin(mrad + mrad + mrad)

    Dim C As Double = sinm * (1.914602 - t * (0.004817 + 0.000014 * t)) + sin2m * (0.019993 - 0.000101 * t) + sin3m * 0.000289
    Return C
    ' in degrees
End Function

'***********************************************************************/
'* Name: SunTrueLongitude   
'* Type: Function   
'* Purpose: calculate the true longitude of the sun 
'* Arguments:   
'* t : number of Julian centuries since J2000.0 
'* Return value:    
'* sun's true longitude in degrees  
'***********************************************************************/


Public Function SunTrueLongitude(t As Double) As Double
    Dim l0 As Double = GemoetricMeanLongitude(t)
    Dim c As Double = SunCentre(t)

    Dim O As Double = l0 + c
    Return O
    ' in degrees
End Function

'***********************************************************************/
'* Name: SunTrueAnomaly 
'* Type: Function   
'* Purpose: calculate the true anamoly of the sun   
'* Arguments:   
'* t : number of Julian centuries since J2000.0 
'* Return value:    
'* sun's true anamoly in degrees    
'***********************************************************************/

Public Function SunTrueAnomaly(t As Double) As Double
    Dim m As Double = GemoetricMeanAnomaly(t)
    Dim c As Double = SunCentre(t)

    Dim v As Double = m + c
    Return v
    ' in degrees
End Function

'***********************************************************************/
'* Name: SunDistanceAU  
'* Type: Function   
'* Purpose: calculate the distance to the sun in AU 
'* Arguments:   
'* t : number of Julian centuries since J2000.0 
'* Return value:    
'* sun radius vector in AUs 
'***********************************************************************/

Public Function SunDistanceAU(t As Double) As Double
    Dim v As Double = SunTrueAnomaly(t)
    Dim e As Double = EarthOrbitEccentricity(t)

    Dim R As Double = (1.000001018 * (1 - e * e)) / (1 + e * Math.Cos(Radians(v)))
    Return R
    ' in AUs
End Function

'***********************************************************************/
'* Name: SunApparentLongitude   
'* Type: Function   
'* Purpose: calculate the apparent longitude of the sun 
'* Arguments:   
'* t : number of Julian centuries since J2000.0 
'* Return value:    
'* sun's apparent longitude in degrees  
'***********************************************************************/

Public Function SunApparentLongitude(t As Double) As Double
    Dim o As Double = SunTrueLongitude(t)

    Dim omega As Double = 125.04 - 1934.136 * t
    Dim lambda As Double = o - 0.00569 - 0.00478 * Math.Sin(Radians(omega))
    Return lambda
    ' in degrees
End Function

'***********************************************************************/
'* Name: MeanObliquityOfEcliptic    
'* Type: Function   
'* Purpose: calculate the mean obliquity of the ecliptic    
'* Arguments:   
'* t : number of Julian centuries since J2000.0 
'* Return value:    
'* mean obliquity in degrees    
'***********************************************************************/

Public Function MeanObliquityOfEcliptic(t As Double) As Double
    Dim seconds As Double = 21.448 - t * (46.815 + t * (0.00059 - t * (0.001813)))
    Dim e0 As Double = 23.0 + (26.0 + (seconds / 60.0)) / 60.0
    Return e0
    ' in degrees
End Function

'***********************************************************************/
'* Name: calcObliquityCorrection    
'* Type: Function   
'* Purpose: calculate the corrected obliquity of the ecliptic   
'* Arguments:   
'* t : number of Julian centuries since J2000.0 
'* Return value:    
'* corrected obliquity in degrees   
'***********************************************************************/

Public Function calcObliquityCorrection(t As Double) As Double
    Dim e0 As Double = MeanObliquityOfEcliptic(t)

    Dim omega As Double = 125.04 - 1934.136 * t
    Dim e As Double = e0 + 0.00256 * Math.Cos(Radians(omega))
    Return e
    ' in degrees
End Function

'***********************************************************************/
'* Name: SunRightAscension  
'* Type: Function   
'* Purpose: calculate the right ascension of the sun    
'* Arguments:   
'* t : number of Julian centuries since J2000.0 
'* Return value:    
'* sun's right ascension in degrees 
'***********************************************************************/

Public Function SunRightAscension(t As Double) As Double
    Dim e As Double = calcObliquityCorrection(t)
    Dim lambda As Double = SunApparentLongitude(t)

    Dim tananum As Double = (Math.Cos(Radians(e)) * Math.Sin(Radians(lambda)))
    Dim tanadenom As Double = (Math.Cos(Radians(lambda)))
    Dim alpha As Double = Degrees(Math.Atan2(tananum, tanadenom))
    Return alpha
    ' in degrees
End Function

'***********************************************************************/
'* Name: SunDeclination 
'* Type: Function   
'* Purpose: calculate the declination of the sun    
'* Arguments:   
'* t : number of Julian centuries since J2000.0 
'* Return value:    
'* sun's declination in degrees 
'***********************************************************************/

Public Function SunDeclination(t As Double) As Double
    Dim e As Double = calcObliquityCorrection(t)
    Dim lambda As Double = SunApparentLongitude(t)

    Dim sint As Double = Math.Sin(Radians(e)) * Math.Sin(Radians(lambda))
    Dim theta As Double = Degrees(Math.Asin(sint))
    Return theta
    ' in degrees
End Function

'***********************************************************************/
'* Name: TrueSolarToMeanSolar   
'* Type: Function   
'* Purpose: calculate the difference between true solar time and mean   
'*   solar time 
'* Arguments:   
'* t : number of Julian centuries since J2000.0 
'* Return value:    
'* equation of time in minutes of time  
'***********************************************************************/

Public Function TrueSolarToMeanSolar(t As Double) As Double
    Dim epsilon As Double = calcObliquityCorrection(t)
    Dim l0 As Double = GemoetricMeanLongitude(t)
    Dim e As Double = EarthOrbitEccentricity(t)
    Dim m As Double = GemoetricMeanAnomaly(t)

    Dim y As Double = Math.Tan(Radians(epsilon) / 2.0)
    y *= y

    Dim sin2l0 As Double = Math.Sin(2.0 * Radians(l0))
    Dim sinm As Double = Math.Sin(Radians(m))
    Dim cos2l0 As Double = Math.Cos(2.0 * Radians(l0))
    Dim sin4l0 As Double = Math.Sin(4.0 * Radians(l0))
    Dim sin2m As Double = Math.Sin(2.0 * Radians(m))

    Dim Etime As Double = y * sin2l0 - 2.0 * e * sinm + 4.0 * e * y * sinm * cos2l0 - 0.5 * y * y * sin4l0 - 1.25 * e * e * sin2m

    Return Degrees(Etime) * 4.0
    ' in minutes of time
End Function

'***********************************************************************/
'* Name: SunriseHourAngle   
'* Type: Function   
'* Purpose: calculate the hour angle of the sun at sunrise for the  
'*   latitude   
'* Arguments:   
'* lat : latitude of observer in degrees    
'*  solarDec : declination angle of sun in degrees  
'* Return value:    
'* hour angle of sunrise in radians 
'***********************************************************************/

Public Function SunriseHourAngle(lat As Double, solarDec As Double) As Double
    Dim latRad As Double = Radians(lat)
    Dim sdRad As Double = Radians(solarDec)

    Dim HAarg As Double = (Math.Cos(Radians(90.833)) / (Math.Cos(latRad) * Math.Cos(sdRad)) - Math.Tan(latRad) * Math.Tan(sdRad))

    Dim HA As Double = (Math.Acos(Math.Cos(Radians(90.833)) / (Math.Cos(latRad) * Math.Cos(sdRad)) - Math.Tan(latRad) * Math.Tan(sdRad)))

    Return HA
    ' in radians
End Function

'***********************************************************************/
'* Name: SunsetHourAngle    
'* Type: Function   
'* Purpose: calculate the hour angle of the sun at sunset for the   
'*   latitude   
'* Arguments:   
'* lat : latitude of observer in degrees    
'*  solarDec : declination angle of sun in degrees  
'* Return value:    
'* hour angle of sunset in radians  
'***********************************************************************/

Public Function SunsetHourAngle(lat As Double, solarDec As Double) As Double
    Dim latRad As Double = Radians(lat)
    Dim sdRad As Double = Radians(solarDec)

    Dim HAarg As Double = (Math.Cos(Radians(90.833)) / (Math.Cos(latRad) * Math.Cos(sdRad)) - Math.Tan(latRad) * Math.Tan(sdRad))

    Dim HA As Double = (Math.Acos(Math.Cos(Radians(90.833)) / (Math.Cos(latRad) * Math.Cos(sdRad)) - Math.Tan(latRad) * Math.Tan(sdRad)))

    Return -HA
    ' in radians
End Function


'***********************************************************************/
'* Name: SunRiseUTC 
'* Type: Function   
'* Purpose: calculate the Universal Coordinated Time (UTC) of sunrise   
'*   for the given day at the given location on earth   
'* Arguments:   
'* julian : julian day  
'* latitude : latitude of observer in degrees   
'* longitude : longitude of observer in degrees 
'* Return value:    
'* time in minutes from zero Z  
'***********************************************************************/

'Public  Function SunRiseUTC(julian As Double, latitude As Double, longitude As Double) As Double
'    Dim t As Double = JulianCenturies(julian)

'    ' *** Find the time of solar noon at the location, and use
'    ' that declination. This is better than start of the 
'    ' Julian day

'    Dim noonmin As Double = SolarNoonUTC(t, longitude)
'    Dim tnoon As Double = JulianCenturies(julian + noonmin / 1440.0)

'    ' *** First pass to approximate sunrise (using solar noon)

'    Dim eqTime As Double = TrueSolarToMeanSolar(tnoon)
'    Dim solarDec As Double = SunDeclination(tnoon)
'    Dim hourAngle As Double = SunriseHourAngle(latitude, solarDec)

'    Dim delta As Double = longitude - Degrees(hourAngle)
'    Dim timeDiff As Double = 4 * delta
'    ' in minutes of time
'    Dim timeUTC As Double = 720 + timeDiff - eqTime
'    ' in minutes
'    ' alert("eqTime = " + eqTime + "\nsolarDec = " + solarDec + "\ntimeUTC = " + timeUTC);

'    ' *** Second pass includes fractional julianay in gamma calc

'    Dim newt As Double = JulianCenturies(JulianDayFromJulianCentury(t) + timeUTC / 1440.0)
'    eqTime = TrueSolarToMeanSolar(newt)
'    solarDec = SunDeclination(newt)
'    hourAngle = SunriseHourAngle(latitude, solarDec)
'    delta = longitude - Degrees(hourAngle)
'    timeDiff = 4 * delta
'    timeUTC = 720 + timeDiff - eqTime
'    ' in minutes
'    ' alert("eqTime = " + eqTime + "\nsolarDec = " + solarDec + "\ntimeUTC = " + timeUTC);

'    Return timeUTC
'End Function

'***********************************************************************/
'* Name: SolarNoonUTC   
'* Type: Function   
'* Purpose: calculate the Universal Coordinated Time (UTC) of solar 
'*   noon for the given day at the given location on earth  
'* Arguments:   
'* t : number of Julian centuries since J2000.0 
'* longitude : longitude of observer in degrees 
'* Return value:    
'* time in minutes from zero Z  
'***********************************************************************/

Public Function SolarNoonUTC(t As Double, longitude As Double) As Double
    ' First pass uses approximate solar noon to calculate eqtime
    Dim tnoon As Double = JulianCenturies(JulianDayFromJulianCentury(t) + longitude / 360.0)
    Dim eqTime As Double = TrueSolarToMeanSolar(tnoon)
    Dim solNoonUTC As Double = 720 + (longitude * 4) - eqTime
    ' min
    Dim newt As Double = JulianCenturies(JulianDayFromJulianCentury(t) - 0.5 + solNoonUTC / 1440.0)

    eqTime = TrueSolarToMeanSolar(newt)
    ' double solarNoonDec = SunDeclination(newt);
    solNoonUTC = 720 + (longitude * 4) - eqTime
    ' min
    Return solNoonUTC
End Function

'***********************************************************************/
'* Name: SunSetUTC  
'* Type: Function   
'* Purpose: calculate the Universal Coordinated Time (UTC) of sunset    
'*   for the given day at the given location on earth   
'* Arguments:   
'* julian : julian day  
'* latitude : latitude of observer in degrees   
'* longitude : longitude of observer in degrees 
'* Return value:    
'* time in minutes from zero Z  
'***********************************************************************/

Public Function SunSetUTC(julian As Double, latitude As Double, longitude As Double) As Double
    Dim t = JulianCenturies(julian)
    Dim eqTime = TrueSolarToMeanSolar(t)
    Dim solarDec = SunDeclination(t)
    Dim hourAngle = SunriseHourAngle(latitude, solarDec)
    hourAngle = -hourAngle
    Dim delta = longitude + Degrees(hourAngle)
    Dim timeUTC = 720 - (4.0 * delta) - eqTime
    ' in minutes
    Return timeUTC
End Function

Public Function SunRiseUTC(julian As Double, latitude As Double, longitude As Double) As Double
    Dim t = JulianCenturies(julian)
    Dim eqTime = TrueSolarToMeanSolar(t)
    Dim solarDec = SunDeclination(t)
    Dim hourAngle = SunriseHourAngle(latitude, solarDec)
    Dim delta = longitude + Degrees(hourAngle)
    Dim timeUTC = 720 - (4.0 * delta) - eqTime
    ' in minutes
    Return timeUTC
End Function

Public Function getTimeString(time As Double, timezone As Integer, julian As Double, dst As Boolean) As String
    Dim timeLocal = time + (timezone * 60.0)
    Dim riseT = JulianCenturies(julian + time / 1440.0)
    timeLocal += (If((dst), 60.0, 0.0))
    Return getTimeString(timeLocal)
End Function

Public Function getDateTime(time As Double, timezone As Integer, [date] As DateTime, dst As Boolean) As System.Nullable(Of DateTime)
    Dim julian As Double = JulianDay([date])
    Dim timeLocal = time + (timezone * 60.0)
    Dim riseT = JulianCenturies(julian + time / 1440.0)
    timeLocal += (If((dst), 60.0, 0.0))
    Return getDateTime(timeLocal, [date])
End Function

Private Function getTimeString(minutes As Double) As String

    Dim output As String = ""

    If (minutes >= 0) AndAlso (minutes < 1440) Then
        Dim floatHour = minutes / 60.0
        Dim hour = Math.Floor(floatHour)
        Dim floatMinute = 60.0 * (floatHour - Math.Floor(floatHour))
        Dim minute = Math.Floor(floatMinute)
        Dim floatSec = 60.0 * (floatMinute - Math.Floor(floatMinute))
        Dim second = Math.Floor(floatSec + 0.5)
        If second > 59 Then
            second = 0
            minute += 1
        End If
        If (second >= 30) Then
            minute += 1
        End If
        If minute > 59 Then
            minute = 0
            hour += 1
        End If
        output = [String].Format("{0:00}:{1:00}", hour, minute)
    Else
        Return "error"
    End If

    Return output
End Function

Private Function getDateTime(minutes As Double, [date] As DateTime) As System.Nullable(Of DateTime)

    Dim retVal As System.Nullable(Of DateTime) = Nothing

    If (minutes >= 0) AndAlso (minutes < 1440) Then
        Dim floatHour = minutes / 60.0
        Dim hour = Math.Floor(floatHour)
        Dim floatMinute = 60.0 * (floatHour - Math.Floor(floatHour))
        Dim minute = Math.Floor(floatMinute)
        Dim floatSec = 60.0 * (floatMinute - Math.Floor(floatMinute))
        Dim second = Math.Floor(floatSec + 0.5)
        If second > 59 Then
            second = 0
            minute += 1
        End If
        If (second >= 30) Then
            minute += 1
        End If
        If minute > 59 Then
            minute = 0
            hour += 1
        End If
        Return New DateTime([date].Year, [date].Month, [date].Day, CInt(hour), CInt(minute), CInt(second))
    Else
        Return retVal
    End If
End Function
End Module

Answer 9

你需要一个公式，其中包括允许地球月球系统围绕太阳的偏心轨道的时间方程。您需要使用具有适当基准点的坐标，例如WGS84或NAD27等。您需要使用JULIAN日历而不是我们每天使用的日历来正确地获取这些时间。在一秒钟内猜测并不容易。我希望有时间在我的位置，阴影长度等于任何高度。当太阳在高中午之前和之后高出地平线60度时，每天应该发生两次。另外，据我所知，你只需要每年添加一天来获得恒星时间，所以如果你想增加你的时钟频率X 366.25 / 365.25你可能现在有一个恒星时钟而不是民用时钟??? “MATH是一个强大的人写了宇宙的语言”

Answer 10

另一个好的JS实现是suncalc。

代码行数是可管理的，因此可以移植到其他语言（C＃）。

Answer 11

如果您更喜欢外部服务，可以使用这个漂亮且免费的日出和日落时间API：http://sunrise-sunset.org/api

我一直在将它用于多个项目并且效果很好，数据似乎非常准确。只需向http://api.sunrise-sunset.org/json

发出HTTP GET请求即可

接受的参数：

lat：十进制度的纬度。必需的。
lng：十进制度的经度。必需的。
日期：YYYY-MM-DD格式的日期。还接受其他日期格式甚至相对日期格式。如果不存在，则日期默认为当前日期。可选的。
回调：JSONP响应的回调函数名称。可选的。
格式化：0或1（默认为1）。响应时间值将根据ISO 8601表示，day_length将以秒表示。可选的。

回应包括日出和日落时间以及黄昏时间。

Answer 12

我在UWP中测试了这个nuget包。

https://www.nuget.org/packages/SolarCalculator/

文档有点粗略，在这里：

https://github.com/porrey/Solar-Calculator

你可以用它来获得日出，给定

la =纬度;和lo =经度;对于您所在地区：

Install-Package SolarCalculator -Version 2.0.2

您可以使用PM管理器在Visual Studio中安装它

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              <div class="col-12">
                <label class="">Employees</label>
                <div class="form-check">
                  <label class="custom-control custom-radio">
                    <input id="radio1" name="radio" type="radio" checked class="custom-control-input">
                    <span class="custom-control-indicator"></span>
                    <span class="custom-control-description"> 0 - 50</span>
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                  <label class="custom-control custom-radio">
                    <input id="radio2" name="radio" type="radio" class="custom-control-input">
                    <span class="custom-control-indicator"></span>
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                    <input id="radio3" name="radio" type="radio" class="custom-control-input">
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                    <span class="custom-control-description">100 - 250</span>
                  </label>
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                    <input id="radio4" name="radio" type="radio" class="custom-control-input">
                    <span class="custom-control-indicator"></span>
                    <span class="custom-control-description">250 - 500</span>
                  </label>
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                    <input id="radio5" name="radio" type="radio" class="custom-control-input">
                    <span class="custom-control-indicator"></span>
                    <span class="custom-control-description">500 - 1000</span>
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                    <input id="radio6" name="radio" type="radio" class="custom-control-input">
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或在＆＃34;管理NuGet包中查找SolarCalculator＆＃34; Visual Studio库。