How to Make textbox/RichTextBox transparent

The problem is:TextboxAndRichTextBoxBackcolorAttributeNot acceptableColor. Transparent. So I giveTextboxAndRichTextBoxControl to find the corresponding solution

This is not a perfect solution. It may be hard for beginners to understand it. If youProgramDesign and C # are good, so this articleArticleIt must be a piece of cake for you.

 

RichTextBox Class Transparentcontrol: Control
{
Public Transparentcontrol ()
{
Base . Setstyle (controlstyles. userpaint, True );
Base . Setstyle (controlstyles. doublebuffer, True );
Base . Setstyle (controlstyles. supportstransparentbackcolor, True );
}
}

ClassTransparentrichtextbox: RichTextBox
{
PublicTransparentrichtextbox ()
{
Base. Scrollbars=Richtextboxscrollbars. None;
}

Override   Protected Createparams
{
Get
{
Createparams CP =   Base . Createparams;
CP. exstyle | =   0x20 ;
Return CP;
}
}

Override Protected VoidOnpaintbackground (painteventargs E)
{
}
}

 

 

Textbox

 

Public   Class Transparenttextbox: textbox
{
Picturebox =   New Picturebox ();

Public Transparenttextbox ()
{
Picturebox. Dock = Dockstyle. Fill;
This . Controls. Add (picturebox );
}
Protected   Override   Void Wndproc ( Ref Message m)
{
Base . Wndproc ( Ref M );
Switch (M. msg)
{
Case Win32.wm _ paint:

Bitmap bmpcaptured =  
New Bitmap ( This . Clientrectangle. Width, This . Clientrectangle. Height );
Bitmap BMP result =  
New Bitmap ( This . Clientrectangle. Width, This . Clientrectangle. Height );
Rectangle R =  
New Rectangle ( 0 , 0 , This . Clientrectangle. Width,
This . Clientrectangle. Height );
 
Capturewindow ( This , Ref Bmpcaptured );
This . Setstyle (controlstyles. supportstransparentbackcolor, True );
This . Backcolor = Color. transparent;

Imageattributes imgattrib= NewImageattributes ();

Colormap [] colormap= NewColormap [1];

Colormap [0]= NewColormap ();

Colormap [0]. Oldcolor=Color. White;

Colormap [0]. Newcolor=Color. transparent;

Imgattrib. setremaptable (colormap );

Graphics g=Graphics. fromimage (BMP result );

G. drawimage (bmpcaptured, R,0,0,This. Clientrectangle. Width,
This. Clientrectangle. Height, graphicsunit. pixel, imgattrib );

G. Dispose ();

Picturebox. Image=(Image) BMP result. Clone ();
Break;

CaseWin32.wm _ hscroll:

CaseWin32.wm _ vscroll:

This. Invalidate ();//Repaint

//If you use scrolling then add these two case statements

Break;
}
}

Private   Static   Void Capturewindow (Control, Ref Bitmap bitmap)
{
Graphics g = Graphics. fromimage (Bitmap );
Int I = ( Int ) (Win32.prf _ Client | Win32.prf _ erasebkgnd );
Intptr iptr =   New Intptr ( 14 );
Intptr HDC = G. gethdc ();
Win32.sendmessage (control. Handle, win32.wm _ print, HDC, iptr );
G. releasehdc (HDC );
G. Dispose ();
}