C# metric transformation

Question

how do i transform inches to pixels and viceversa ? if it was c++ i'd use the device context functions lptodp and lptohimetric but i need a C# solution.

Mahesh Chand · Answer

Look at Trasnform method of Graphics and its related objects. Also there are some articles in GDI+ section of this site on transformation.

gaby2r · Answer

thise articles only show how to work with the graphics class. however what i needed wasn't related to drawing something i just needed to change 3 values. but i wasn't wrong graphics class was the place to look. the transform functions held the answers. i used transformpoints function. here is the code: Graphics g=this.CreateGraphics(); g.PageUnit=GraphicsUnit.Inch; g.PageScale=1; PointF[] bottom=new PointF[3]; bottom[0]=new PointF((float)this.pageSetupDialog1.PageSettings.PaperSize.Width/1001); bottom[1]=new PointF((float)this.pageSetupDialog1.PageSettings.Margins.Left/1001); bottom[2]=new PointF((float)this.pageSetupDialog1.PageSettings.Margins.Right/1001); g.TransformPoints(CoordinateSpace.DeviceCoordinateSpace.Pagebottom); g.Dispose(); int pixelix=(int)bottom[0].X; this.outputrichbox.ClientSize=new Size(pixelixthis.outputrichbox.ClientSize.Height); pixelix=(int)bottom[1].X; this.outputrichbox.SelectionIndent=(int)pixelix; pixelix=(int)bottom[2].X; this.outputrichbox.SelectionRightIndent=(int)pixelix; this.Refresh(); at first i thought this was the soultion since the box resized accordingly to the paper size i selected in the pageSetupDialog but .. when i compared the text to the printed version .. things were a bit diferent. since almoust everything else is correct i must assume that richtextbox.ClientSize.Width is not measured in pixels. does anyone have an idea about this? thanks in advance.

mibuyt · Answer

Hi Have you seen this? Since you want to do some transformation related to graphics class. Pen p=new Pen(Color.Black1.0f); e.Graphics.PageUnit=GraphicsUnit.Pixel; e.Graphics.DrawLine(p101030010); e.Graphics.PageUnit=GraphicsUnit.Point; e.Graphics.DrawLine(p107230072); e.Graphics.PageUnit=GraphicsUnit.Millimeter; e.Graphics.DrawLine(p102010020); e.Graphics.PageUnit=GraphicsUnit.Inch; e.Graphics.DrawLine(p0.25f262); For more info look at this. http://www.bobpowell.net/scalepens.htm http://www.bobpowell.net/tbscaling.htm http://msdn.microsoft.com/library/default.asp?url=/library/en-us/cpguide/html/_gdiplus_types_of_coordinate_systems_about.asp Hope it helps! Cheers.

gaby2r · Answer

since i've got no reply i must figure these questions are too complex so here is the context behid the problem: i need to resize some richtextboxes to an exact size(on screen). the thing is the size i need to set it to is in inches and i need pixels (because richtextbox.size.width(or height) is in pixels). normaly you would expect the graphics class to have such transformation functions because these depend on the dpi of the device context but unless i'm missing something i can't find them!!