C Get a control s position on a form

Question

Is there any way to retrieve a control s position in a form  when the control may be inside other controls  like Panels    The control s Left and Top properties gives me only it s position within it s parent control  but what if my control is inside five nested panels  and I need it s position on the form   Quick example   The button btnA is located on coordinates  10 10  inside the panel pnlB  The panel pnlB is located on coordinates  15 15  inside the form frmC   I want btnA s location on frmC  which is  25 25    Can I get this location

User · Answer

You could walk up through the parents  noting their position within their parent  until you arrive at the Form   Edit  Something like  untested    public Point GetPositionInForm Control ctrl       Point p   ctrl Location     Control parent   ctrl Parent     while     parent is Form              p Offset parent Location X  parent Location Y         parent   parent Parent          return p

User · Answer

Supergeek  your non recursive function did not producte the correct result  but mine does  I believe yours does one too many additions   private Point LocationOnClient Control c       Point retval   new Point 0  0      for    c Parent    null  c   c Parent       retval Offset c Location        return retval

User · Answer

In my testing  both Hans Kesting s and Fredrik M  rk s solutions gave the same answer   But   I found an interesting discrepancy in the answer using the methods of Raj More and Hans Kesting  and thought I d share   Thanks to both though for their help  I can t believe such a method is not built into the framework   Please note that Raj didn t write code and therefore my implementation could be different than he meant   The difference I found was that the method from Raj More would often be two pixels greater  in both X and Y  than the method from Hans Kesting   I have not yet determined why this occurs   I m pretty sure it has something to do with the fact that there seems to be a two-pixel border around the contents of a Windows form  as in  inside the form s outermost borders    In my testing  which was certainly not exhaustive to any extent  I ve only come across it on controls that were nested   However  not all nested controls exhibit it   For example  I have a TextBox inside a GroupBox which exhibits the discrepancy  but a Button inside the same GroupBox does not   I cannot explain why   Note that when the answers are equivalent  they consider the point  0  0  to be inside the content border I mentioned above   Therefore I believe I ll consider the solutions from Hans Kesting and Fredrik M  rk to be correct but don t think I ll trust the solution I ve implemented of Raj More s   I also wondered exactly what code Raj More would have written  since he gave an idea but didn t provide code   I didn t fully understand the PointToScreen   method until I read this post  http   social msdn microsoft com Forums en-US netfxcompact thread aa91d4d8-e106-48d1-8e8a-59579e14f495  Here s my method for testing   Note that  Method 1  mentioned in the comments is slightly different than Hans Kesting s   private Point GetLocationRelativeToForm Control c         Method 1  walk up the control tree   Point controlLocationRelativeToForm1   new Point      Control currentControl   c    while  currentControl Parent    null          controlLocationRelativeToForm1 Offset currentControl Left  currentControl Top       currentControl   currentControl Parent            Method 2  determine absolute position on screen of control and form  and calculate difference   Point controlScreenPoint   c PointToScreen Point Empty     Point formScreenPoint   PointToScreen Point Empty     Point controlLocationRelativeToForm2   controlScreenPoint - new Size formScreenPoint         Method 3  combine PointToScreen   and PointToClient     Point locationOnForm   c FindForm   PointToClient c Parent PointToScreen c Location          Theoretically they should be the same   Debug Assert controlLocationRelativeToForm1    controlLocationRelativeToForm2     Debug Assert locationOnForm    controlLocationRelativeToForm1     Debug Assert locationOnForm    controlLocationRelativeToForm2      return controlLocationRelativeToForm1

User · Answer

Oddly enough  PointToClient and PointToScreen weren t ideal for my situation   Particularly because I m working with offscreen controls that aren t associated with any form   I found sahin s solution the most helpful  but took out recursion and eliminated the Form termination   The solution below works for any of my controls visible or not  Form-contained or not  IContainered or not   Thanks Sahim   private static Point FindLocation Control ctrl        Point p      for  p   ctrl Location  ctrl Parent    null  ctrl   ctrl Parent          p Offset ctrl Parent Location       return p

User · Answer

I usually combine PointToScreen and PointToClient   Point locationOnForm   control FindForm   PointToClient      control Parent PointToScreen control Location

User · Answer

I usually do it like this   Works every time    var loc   ctrl PointToScreen Point Empty

User · Answer

You can use the controls PointToScreen method to get the absolute position with respect to the screen   You can do the Forms PointToScreen method  and with basic math  get the control s position

User · Answer

private Point FindLocation Control ctrl        if  ctrl Parent is Form          return ctrl Location      else               Point p   FindLocation ctrl Parent           p X    ctrl Location X          p Y    ctrl Location Y          return p

User · Answer

This is what i ve done  works like a charm              private static int  x 0   y 0          private static Point  point          public static Point LocationInForm Control c                        if  c Parent    null                                  x    c Location X                   y    c Location Y                   point   new Point  x   y                    x   0   y   0                  return  point                            else if   c Parent is System Windows Forms Form                                  point   new Point  x   y                    x   0   y   0                  return  point                            else                                 x    c Location X                   y    c Location Y                  LocationInForm c Parent                             return new Point 1 1

[c#] C# Get a control's position on a form

Examples related to c#

Examples related to winforms

Examples related to controls