using a PointF type object in a Property

using a PointF type object in a Property

• Silvina7407

  If you were to create a new PointF 10x a second your code wouldn’t be as efficient as it could be... but then is that really a problem

  Like so many possibilities of performance issues your best bet would be to do a little testing and determine some metrics for how bad creating 10 PointF’s a second every second would be for your application vs having a couple of properties that allow you direct access to the X and Y components. My guess... it wouldn’t be that bad.

  
  
  

• wjvii

  Ah, I think I got you.
  
  So, in order to change the values of a value type object, a new object of that same type has to be instantiated
  
  Thanks,
  
  - Alex
  
  
  

• ParthasarathyT1980

  You are partially correct with regards to what n0n4m3 said. You can easily change the properties of a value type as we see in shakalama’s example (which may be one way for you to fix your problem).

  The problem with setting a part of a value type without rebuilding it is with properties because to set the single value of the value type the property has to return the entire struct and then make available the individual value... when you try to set it the system doesn’t know what to do with this value as you are effectively setting (in your example) a float to a property that only accepts values of the type PointF.

  Does this make things a little more clear

  
  
  

• Namviet

  Hi,
  the reason why you can't do that is because PointF is a value type and so, the get property returns a copy of that struct. The compiler prevents you from changing that copy because it wouldn't work as you expected. To change that property you have to do it like this:
  
  SholderPoint = new PointF(10.0f, 20.0f);
  
  
  

• Rob the programmer

  That does clear things up a bit.
  
  I guess my only question is this. If I have the properties being set using:
  
  SholderPoint = new PointF(X, Y);
  
  inside a loop from a timer (about 100ms ticks) that is constantly running and recalculating the new PointF values, won't my loop end up quite inefficient, because the garbage collector cannot dispose of the objects quick enough and probably many other reasons that I'm not aware of
  
  
  
  
  

• MarkChu

  hi,

  x and y are properties , i think you have to expose x and y in your application in properties as well like for example

  private static PointF _point;

  public static float myX

  {

  get { return _point.X; }

  set { _point.X = value; }

  }

  public static PointF MyPoint

  {

  get { return _point; }

  set { _point = value; }

  }

  hope this helps

  
  
  

• Vadim Pokotilov

  Find discussion on same topic @

  http://www.codecomments.com/archive290-2005-5-503021.html

  
  
  
• using a PointF type object in a Property