Calculating XY positions and setting boundries

Question

Hey This is my problem: I want to set several star objects at random and within certain boundry in window using 2 classes. One class is for checking position: ************************************************** using System; using Microsoft.DirectX; using Microsoft.DirectX.Direct3D; namespace Starglider { public class CObjPos { private Vector2 position; private Vector2 screenSize; private Vector2 finalPos; private Random rndstar; private int xwidth; private int yheight; //based on the windows width and height. trying to pass in public CObjPos(int width, int height) { xwidth = width; yheight = height; } //these methods checks other objects position private void CalcXOffset() { finalPos.X = position.X - (screenSize.X / 2); //calculates the final offset of x in the center of screen } private void CalcYOffset() { finalPos.Y = position.Y - (screenSize.Y / 2); //calculates the final offset of y in the center of screen } private void CalcStarXOffset() { rndstar = new Random(); //how do i calculate position based on the windows width and at random? position.X = rndstar.Next(xwidth); //readablity when i've defined the finalpos as it is based on what value position has. finalPos.X = position.X; //supposed to check boundry so that it only set stars within the width of the window. I dont think it works though. if (finalPos.X >= xwidth) { finalPos.X = 0; } } //same here private void CalcStarYOffset() { rndstar = new Random(); //height? position.Y = rndstar.Next(yheight); finalPos.Y = position.Y; //same as last one. if (finalPos.Y >= yheight) { finalPos.Y = 0; } } public float X { get {return position.X;} set {position.X = value; CalcXOffset();} } public float Y { get {return position.Y;} set {position.Y = value; CalcYOffset();} } public float StarXPos { set {finalPos.X = value; CalcStarXOffset();} } public float StarYPos { set {finalPos.Y = value; CalcStarYOffset();} } **************************************** The other class is only a sprite class for drawing the things i want to draw and a third class, namely the mainwindow(form) class where the form properties are.. Question 1 How do i set the stars object at random and within a specified boundry?