经纬度坐标与高斯坐标的转换VB代码

在VB中，经纬度坐标和高斯投影坐标的转换通常需要使用第三方库，因为VB 6.0标准库并不内置这种复杂的空间几何计算能力。以下是一个简单的示例，使用.Net Framework的`NetTopologySuite`库来进行转换。请注意，这只是一个基础示例，实际应用可能需要根据具体的投影类型和库函数来调整。

Imports NetTopologySuite.Geometries
Imports NetTopologySuite.CoordinateTransformation

Public Function LatLonToUTM(ByVal lat As Double, ByVal lon As Double, ByVal zoneNumber As Integer, ByVal hemisphere As String) As Coordinate
    Dim ellipsoid As Ellipsoid = Ellipsoids.WGS84
    Dim geographicCoordinate As Coordinate = New Coordinate(lon, lat, ellipsoid.SemiMajorAxis)
    Dim datum As Datum = DatumFactory.CreateDatum(hemisphere, ellipsoid)
    Dim transformer As IAffineTransformation = datum.ToWgs84().GetMathTransform(datum)

    ' 转换到UTM（统一横轴墨卡托坐标）
    Dim utmCoordinate As Coordinate = transformer.Transform(geographicCoordinate)

    ' 区域码和中央经线偏移
    DimutmZone As Integer = Math.Floor((lon + 180) / 6) - (If(lon > 0, 6, 5)) ' East/West zones differ by 1
    Dim centralMeridian As Double = If(utmZone Mod 2 = 0, 3 * 60 - (lon % 6), 3 * 60 + (lon % 6))

    ' 计算X、Y坐标并加上中央经线偏移
    Dim x As Double = utmCoordinate.X - centralMeridian
    Dim y As Double = utmCoordinate.Y

    ' 返回高斯坐标
    Return New Coordinate(x, y, ellipsoid.SemiMajorAxis)
End Function

' 示例中，zoneNumber表示UTM区号，hemisphere可以是"N"或"S"
' 比如LatLonToUTM(40.7128, -74.0060, 18, "N") 应该返回对应纽约曼哈顿的UTM坐标