From Xojo Documentation

Property (As Double )
aCurveShape.X2 = newDoubleValue
DoubleValue = aCurveShape.X2

Supported for all project types and targets.

The horizontal position of the end of the line or curve.

Sample Code

The following method is in the Paint event of a Window. It draws a simple curve. The negative value of ControlY(0) places the control point above the imaginary straight line from x,y to x2,y2.

Var c As New CurveShape
c.ControlX(0) = 120
c.ControlY(0) = -40
c.Order = 1
c.X = 10
c.Y = 100
c.X2 = 250
c.Y2 = 100

g.DrawObject(c, c.X, c.Y)