Lines
The ILine interface represents a line between two instances of IPoint. For instance, you could initialize a new line like:
// Initialize two points by latitude and longitude
IPoint a = new Point(55.708151, 9.536131);
IPoint b = new Point(55.708069, 9.536000);
// Initialize a new line from the two points
ILine line = new Line(a, b);
The ILine interface gives you a few options - such as using the GetLength method for determining the length of said line:
// Calculate the length of the line in metres
double length = line.GetLength();
The interface also defines a GetCenter method to get the center point of the line:
// Calculate the center point of the line
IPoint center = line.GetCenter();
Finally you can also use the GetBoundingBox method to get an instance of IRectangle that contains the line:
// Calculate the bounding box of the line
IRectangle boundingBox = line.GetBoundingBox();
Line strings
Where the ILine interface represents a single line between two points, the ILineString interface describes a collection of connected lines - this is typically called a line string or a polyline (similar to a polygon).
// Initialize the points by latitude and longitude
IPoint a = new Point(55.69924, 9.55798);
IPoint b = new Point(55.69341, 9.57227);
IPoint c = new Point(55.69065, 9.58866);
IPoint d = new Point(55.69338, 9.60939);
// Initialize a new line string from the four points
ILineString lineString = new LineString(a, b, c, d);
Similar to ILine, the ILineString interfaces lets you call the GetLength, GetCenter and GetBoundingBox methods:
// Calculate the length of the line string in metres
double length = lineString.GetLength();
// Calculate the center point of the line string
IPoint center = lineString.GetCenter();
// Calculate the bounding box of the line string
IRectangle boundingBox = lineString.GetBoundingBox();