（二十九）c#Winform自定义控件-文本框（二）

前提

入行已经7,8年了，一直想做一套漂亮点的自定义控件，于是就有了本系列文章。

开源地址：

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目录

准备工作

终于到文本框了，文本框将包含原文本框扩展，透明文本框，数字输入文本框，带边框文本框

本文将讲解透明文本框

开始

这个用到的很少，直接看代码吧

  1 // 版权所有  黄正辉  交流群：568015492   qq：623128629
  2 // 文件名称：textboxtransparent.cs
  3 // 创建日期：2019-08-15 16:03:49
  4 // 功能描述：textbox
  5 // 项目地址：https://gitee.com/kwwwvagaa/net_winform_custom_control
  6 using system;
  7 using system.collections;
  8 using system.componentmodel;
  9 using system.drawing;
 10 using system.data;
 11 using system.windows.forms;
 12 
 13 using system.drawing.imaging;
 14 
 15 namespace hzh_controls.controls
 16 {
 17     public class textboxtransparent : textboxex
 18     {
 19         #region private variables
 20 
 21         private upicturebox mypicturebox;
 22         private bool myuptodate = false;
 23         private bool mycaretuptodate = false;
 24         private bitmap mybitmap;
 25         private bitmap myalphabitmap;
 26 
 27         private int myfontheight = 10;
 28 
 29         private system.windows.forms.timer mytimer1;
 30 
 31         private bool mycaretstate = true;
 32 
 33         private bool mypaintedfirsttime = false;
 34 
 35         private color mybackcolor = color.white;
 36         private int mybackalpha = 10;
 37 
 38         /// <summary> 
 39         /// required designer variable.
 40         /// </summary>
 41         private system.componentmodel.container components = null;
 42 
 43         #endregion // end private variables
 44 
 45 
 46         #region public methods and overrides
 47 
 48         public textboxtransparent()
 49         {
 50             // this call is required by the windows.forms form designer.
 51             initializecomponent();
 52             // todo: add any initialization after the initializecomponent call
 53 
 54             this.backcolor = mybackcolor;
 55 
 56             this.setstyle(controlstyles.userpaint, false);
 57             this.setstyle(controlstyles.allpaintinginwmpaint, true);
 58             this.setstyle(controlstyles.doublebuffer, true);
 59 
 60 
 61             mypicturebox = new upicturebox();
 62             this.controls.add(mypicturebox);
 63             mypicturebox.dock = dockstyle.fill;
 64         }
 65 
 66 
 67         protected override void onresize(eventargs e)
 68         {
 69 
 70             base.onresize(e);
 71             this.mybitmap = new bitmap(this.clientrectangle.width, this.clientrectangle.height);//(this.width,this.height);
 72             this.myalphabitmap = new bitmap(this.clientrectangle.width, this.clientrectangle.height);//(this.width,this.height);
 73             myuptodate = false;
 74             this.invalidate();
 75         }
 76 
 77 
 78         //some of these should be moved to the wndproc later
 79 
 80         protected override void onkeydown(keyeventargs e)
 81         {
 82             base.onkeydown(e);
 83             myuptodate = false;
 84             this.invalidate();
 85         }
 86 
 87         protected override void onkeyup(keyeventargs e)
 88         {
 89             base.onkeyup(e);
 90             myuptodate = false;
 91             this.invalidate();
 92 
 93         }
 94 
 95         protected override void onkeypress(keypresseventargs e)
 96         {
 97             base.onkeypress(e);
 98             myuptodate = false;
 99             this.invalidate();
100         }
101 
102         protected override void onmouseup(mouseeventargs e)
103         {
104             base.onmouseup(e);
105             this.invalidate();
106         }
107 
108         protected override void ongivefeedback(givefeedbackeventargs gfbevent)
109         {
110             base.ongivefeedback(gfbevent);
111             myuptodate = false;
112             this.invalidate();
113         }
114 
115 
116         protected override void onmouseleave(eventargs e)
117         {
118             //found this code to find the current cursor location
119             //at http://www.syncfusion.com/faq/winforms/faq_c50c.asp#q597q
120 
121             point ptcursor = cursor.position;
122 
123             form f = this.findform();
124             ptcursor = f.pointtoclient(ptcursor);
125             if (!this.bounds.contains(ptcursor))
126                 base.onmouseleave(e);
127         }
128 
129 
130         protected override void onchangeuicues(uicueseventargs e)
131         {
132             base.onchangeuicues(e);
133             myuptodate = false;
134             this.invalidate();
135         }
136 
137 
138         //--
139         protected override void ongotfocus(eventargs e)
140         {
141             base.ongotfocus(e);
142             mycaretuptodate = false;
143             myuptodate = false;
144             this.invalidate();
145 
146 
147             mytimer1 = new system.windows.forms.timer(this.components);
148             mytimer1.interval = (int)win32.getcaretblinktime(); //  usually around 500;
149 
150             mytimer1.tick += new eventhandler(mytimer1_tick);
151             mytimer1.enabled = true;
152 
153         }
154 
155         protected override void onlostfocus(eventargs e)
156         {
157             base.onlostfocus(e);
158             mycaretuptodate = false;
159             myuptodate = false;
160             this.invalidate();
161 
162             mytimer1.dispose();
163         }
164 
165         //--        
166 
167         protected override void onfontchanged(eventargs e)
168         {
169             if (this.mypaintedfirsttime)
170                 this.setstyle(controlstyles.userpaint, false);
171 
172             base.onfontchanged(e);
173 
174             if (this.mypaintedfirsttime)
175                 this.setstyle(controlstyles.userpaint, true);
176 
177 
178             myfontheight = getfontheight();
179 
180 
181             myuptodate = false;
182             this.invalidate();
183         }
184 
185         protected override void ontextchanged(eventargs e)
186         {
187             base.ontextchanged(e);
188             myuptodate = false;
189             this.invalidate();
190         }
191 
192 
193         protected override void wndproc(ref message m)
194         {
195 
196             base.wndproc(ref m);
197 
198             // need to rewrite as a big switch
199 
200             if (m.msg == win32.wm_paint)
201             {
202 
203                 mypaintedfirsttime = true;
204 
205                 if (!myuptodate || !mycaretuptodate)
206                     getbitmaps();
207                 myuptodate = true;
208                 mycaretuptodate = true;
209 
210                 if (mypicturebox.image != null) mypicturebox.image.dispose();
211 
212 
213                 if (string.isnullorempty(this.text) && !string.isnullorempty(this.prompttext))
214                 {
215                     bitmap bit = (bitmap)myalphabitmap.clone();
216                     graphics g = graphics.fromimage(bit);
217                     sizef sizet1 = g.measurestring(this.prompttext, this.promptfont);
218                     g.drawstring(this.prompttext, this.promptfont, new solidbrush(promptcolor), new pointf(3, (bit.height - sizet1.height) / 2));
219                     g.dispose();
220                     mypicturebox.image = bit;
221                 }
222                 else
223                 {
224                     mypicturebox.image = (image)myalphabitmap.clone();
225                 }
226             }
227 
228             else if (m.msg == win32.wm_hscroll || m.msg == win32.wm_vscroll)
229             {
230                 myuptodate = false;
231                 this.invalidate();
232             }
233 
234             else if (m.msg == win32.wm_lbuttondown
235                 || m.msg == win32.wm_rbuttondown
236                 || m.msg == win32.wm_lbuttondblclk
237                 //  || m.msg == win32.wm_mouseleave  ///****
238                 )
239             {
240                 myuptodate = false;
241                 this.invalidate();
242             }
243 
244             else if (m.msg == win32.wm_mousemove)
245             {
246                 if (m.wparam.toint32() != 0)  //shift key or other buttons
247                 {
248                     myuptodate = false;
249                     this.invalidate();
250                 }
251             }
252 
253             if (m.msg == 15 || m.msg == 7 || m.msg == 8)
254             {
255                 base.onpaint(null);
256             }
257 
258             //system.diagnostics.debug.writeline("pro: " + m.msg.tostring("x"));
259 
260         }
261 
262 
263         /// <summary> 
264         /// clean up any resources being used.
265         /// </summary>
266         protected override void dispose(bool disposing)
267         {
268             if (disposing)
269             {
270                 //this.backcolor = color.pink;
271                 if (components != null)
272                 {
273                     components.dispose();
274                 }
275             }
276             base.dispose(disposing);
277         }
278 
279         #endregion        //end public method and overrides
280 
281 
282         #region public property overrides
283 
284         public new borderstyle borderstyle
285         {
286             get { return base.borderstyle; }
287             set
288             {
289                 if (this.mypaintedfirsttime)
290                     this.setstyle(controlstyles.userpaint, false);
291 
292                 base.borderstyle = value;
293 
294                 if (this.mypaintedfirsttime)
295                     this.setstyle(controlstyles.userpaint, true);
296 
297                 this.mybitmap = null;
298                 this.myalphabitmap = null;
299                 myuptodate = false;
300                 this.invalidate();
301             }
302         }
303 
304         public new color backcolor
305         {
306             get
307             {
308                 return color.fromargb(base.backcolor.r, base.backcolor.g, base.backcolor.b);
309             }
310             set
311             {
312                 mybackcolor = value;
313                 base.backcolor = value;
314                 myuptodate = false;
315             }
316         }
317         public override bool multiline
318         {
319             get { return base.multiline; }
320             set
321             {
322                 if (this.mypaintedfirsttime)
323                     this.setstyle(controlstyles.userpaint, false);
324 
325                 base.multiline = value;
326 
327                 if (this.mypaintedfirsttime)
328                     this.setstyle(controlstyles.userpaint, true);
329 
330                 this.mybitmap = null;
331                 this.myalphabitmap = null;
332                 myuptodate = false;
333                 this.invalidate();
334             }
335         }
336 
337 
338         #endregion    //end public property overrides
339 
340 
341         #region private functions and classes
342 
343         private int getfontheight()
344         {
345             graphics g = this.creategraphics();
346             sizef sf_font = g.measurestring("x", this.font);
347             g.dispose();
348             return (int)sf_font.height;
349         }
350 
351 
352         private void getbitmaps()
353         {
354 
355             if (mybitmap == null
356                 || myalphabitmap == null
357                 || mybitmap.width != width
358                 || mybitmap.height != height
359                 || myalphabitmap.width != width
360                 || myalphabitmap.height != height)
361             {
362                 mybitmap = null;
363                 myalphabitmap = null;
364             }
365 
366 
367 
368             if (mybitmap == null)
369             {
370                 mybitmap = new bitmap(this.clientrectangle.width, this.clientrectangle.height);//(width,height);
371                 myuptodate = false;
372             }
373 
374 
375             if (!myuptodate)
376             {
377                 //capture the textbox control window
378 
379                 this.setstyle(controlstyles.userpaint, false);
380 
381                 win32.capturewindow(this, ref mybitmap);
382 
383                 this.setstyle(controlstyles.userpaint, true);
384                 this.setstyle(controlstyles.supportstransparentbackcolor, true);
385                 this.backcolor = color.fromargb(mybackalpha, mybackcolor);
386 
387             }
388             //--
389 
390 
391 
392             rectangle r2 = new rectangle(0, 0, this.clientrectangle.width, this.clientrectangle.height);
393             imageattributes tempimageattr = new imageattributes();
394 
395 
396             //found the color map code in the ms help
397 
398             colormap[] tempcolormap = new colormap[1];
399             tempcolormap[0] = new colormap();
400             tempcolormap[0].oldcolor = color.fromargb(255, mybackcolor);
401             tempcolormap[0].newcolor = color.fromargb(mybackalpha, mybackcolor);
402 
403             tempimageattr.setremaptable(tempcolormap);
404 
405             if (myalphabitmap != null)
406                 myalphabitmap.dispose();
407 
408 
409             myalphabitmap = new bitmap(this.clientrectangle.width, this.clientrectangle.height);//(width,height);
410 
411             graphics tempgraphics1 = graphics.fromimage(myalphabitmap);
412 
413             tempgraphics1.drawimage(mybitmap, r2, 0, 0, this.clientrectangle.width, this.clientrectangle.height, graphicsunit.pixel, tempimageattr);
414 
415             tempgraphics1.dispose();
416 
417             //----
418 
419             if (this.focused && (this.selectionlength == 0))
420             {
421                 graphics tempgraphics2 = graphics.fromimage(myalphabitmap);
422                 if (mycaretstate)
423                 {
424                     //draw the caret
425                     point caret = this.findcaret();
426                     pen p = new pen(this.forecolor, 3);
427                     tempgraphics2.drawline(p, caret.x + 2, caret.y + 0, caret.x + 2, caret.y + myfontheight);
428                     tempgraphics2.dispose();
429                 }
430 
431             }
432 
433 
434 
435         }
436 
437 
438 
439         private point findcaret()
440         {
441             /*  find the caret translated from code at 
442              * http://www.vb-helper.com/howto_track_textbox_caret.html
443              * 
444              * and 
445              * 
446              * http://www.microbion.co.uk/developers/csharp/textpos2.htm
447              * 
448              * changed to em_posfromchar
449              * 
450              * this code still needs to be cleaned up and debugged
451              * */
452 
453             point pointcaret = new point(0);
454             int i_char_loc = this.selectionstart;
455             intptr pi_char_loc = new intptr(i_char_loc);
456 
457             int i_point = win32.sendmessage(this.handle, win32.em_posfromchar, pi_char_loc, intptr.zero);
458             pointcaret = new point(i_point);
459 
460             if (i_char_loc == 0)
461             {
462                 pointcaret = new point(0);
463             }
464             else if (i_char_loc >= this.text.length)
465             {
466                 pi_char_loc = new intptr(i_char_loc - 1);
467                 i_point = win32.sendmessage(this.handle, win32.em_posfromchar, pi_char_loc, intptr.zero);
468                 pointcaret = new point(i_point);
469 
470                 graphics g = this.creategraphics();
471                 string t1 = this.text.substring(this.text.length - 1, 1) + "x";
472                 sizef sizet1 = g.measurestring(t1, this.font);
473                 sizef sizex = g.measurestring("x", this.font);
474                 g.dispose();
475                 int xoffset = (int)(sizet1.width - sizex.width);
476                 pointcaret.x = pointcaret.x + xoffset;
477 
478                 if (i_char_loc == this.text.length)
479                 {
480                     string slast = this.text.substring(text.length - 1, 1);
481                     if (slast == "\n")
482                     {
483                         pointcaret.x = 1;
484                         pointcaret.y = pointcaret.y + myfontheight;
485                     }
486                 }
487 
488             }
489 
490 
491 
492             return pointcaret;
493         }
494 
495 
496         private void mytimer1_tick(object sender, eventargs e)
497         {
498             //timer used to turn caret on and off for focused control
499 
500             mycaretstate = !mycaretstate;
501             mycaretuptodate = false;
502             this.invalidate();
503         }
504 
505 
506         private class upicturebox : picturebox
507         {
508             public upicturebox()
509             {
510                 this.setstyle(controlstyles.selectable, false);
511                 this.setstyle(controlstyles.userpaint, true);
512                 this.setstyle(controlstyles.allpaintinginwmpaint, true);
513                 this.setstyle(controlstyles.doublebuffer, true);
514 
515                 this.cursor = null;
516                 this.enabled = true;
517                 this.sizemode = pictureboxsizemode.normal;
518 
519             }
520 
521 
522 
523 
524             //upicturebox
525             protected override void wndproc(ref message m)
526             {
527                 if (m.msg == win32.wm_lbuttondown
528                     || m.msg == win32.wm_rbuttondown
529                     || m.msg == win32.wm_lbuttondblclk
530                     || m.msg == win32.wm_mouseleave
531                     || m.msg == win32.wm_mousemove)
532                 {
533                     //send the above messages back to the parent control
534                     win32.postmessage(this.parent.handle, (uint)m.msg, m.wparam, m.lparam);
535                 }
536 
537                 else if (m.msg == win32.wm_lbuttonup)
538                 {
539                     //??  for selects and such
540                     this.parent.invalidate();
541                 }
542 
543 
544                 base.wndproc(ref m);
545             }
546 
547 
548         }   // end upicturebox class
549 
550 
551         #endregion  // end private functions and classes
552 
553 
554         #region component designer generated code
555         /// <summary> 
556         /// required method for designer support - do not modify 
557         /// the contents of this method with the code editor.
558         /// </summary>
559         private void initializecomponent()
560         {
561             components = new system.componentmodel.container();
562         }
563         #endregion
564 
565 
566         #region new public properties
567 
568         [
569         category("appearance"),
570         description("the alpha value used to blend the control's background. valid values are 0 through 255."),
571         browsable(true),
572         designerserializationvisibility(designerserializationvisibility.visible)
573 
574         ]
575         public int backalpha
576         {
577             get { return mybackalpha; }
578             set
579             {
580                 int v = value;
581                 if (v > 255)
582                     v = 255;
583                 mybackalpha = v;
584                 myuptodate = false;
585                 invalidate();
586             }
587         }
588 
589         #endregion
590 
591 
592 
593     }  // end alphatextbox class 
594 }

 

用处及效果

用到的比较少，你高兴就用，哈哈

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