C# 4 and .NET 4

962 ❘ ChaPTer 34 .net prOGrAmminG with sQl server
}
return null;
char northSouth = longitude > 0 'N': 'S';
char eastWest = latitude > 0 'E': 'W';
int longitudeDegrees = Math.Abs(longitude) / 3600;
int remainingSeconds = Math.Abs(longitude) % 3600;
int longitudeMinutes = remainingSeconds / 60;
int longitudeSeconds = remainingSeconds % 60;
int latitudeDegrees = Math.Abs(latitude) / 3600;
remainingSeconds = Math.Abs(latitude) % 3600;
int latitudeMinutes = remainingSeconds / 60;
int latitudeSeconds = remainingSeconds % 60;
return String.Format("{0}˚{1}'{2}\"{3},{4}˚{5}'{6}\"{7}",
longitudeDegrees, longitudeMinutes, longitudeSeconds,
northSouth, latitudeDegrees, latitudeMinutes,
latitudeSeconds, eastWest);
Conversion from a string happens with the Parse() method. The string that is entered from the user
is represented in the SqlString parameter of the static method Parse(). First, the Parse() method
checks if the string represents a null value, in which case the Null property is invoked to return an empty
SqlCoordinate object. If the SqlString s does not represent a null value, the text of the string is
converted to pass the longitude and latitude values to the SqlCoordinate constructor:
public static SqlCoordinate Parse(SqlString s)
{
if (s.IsNull)
return SqlCoordinate.Null;
try
{
string[] coordinates = s.Value.Split(',');
char[] separators = { '˚', '\'', '\"' };
string[] longitudeVals = coordinates[0].Split(separators);
string[] latitudeVals = coordinates[1].Split(separators);
if (longitudeVals.Length != 4 && latitudeVals.Length != 4)
throw new ArgumentException(
"Argument has a wrong syntax. " +
"This syntax is required: 37˚47\'0\"N,122˚26\'0\"W");
Orientation orientation;
if (longitudeVals[3] == "N" && latitudeVals[3] == "E")
orientation = Orientation.NorthEast;
else if (longitudeVals[3] == "S" && latitudeVals[3] == "W")
orientation = Orientation.SouthWest;
else if (longitudeVals[3] == "S" && latitudeVals[3] == "E")
orientation = Orientation.SouthEast;
else
orientation = Orientation.NorthWest;
return new SqlCoordinate(
int.Parse(longitudeVals[0]), int.Parse(longitudeVals[1]),
int.Parse(longitudeVals[2]),
int.Parse(latitudeVals[0]), int.Parse(latitudeVals[1]),
int.Parse(latitudeVals[2]), orientation);
}
catch (FormatException ex)
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