lion-tutorial33.htm

内有一些代码

  you have at most three choices: </font></p>
<ol>
  <li><font face="Tahoma" size="-1">Apply to all text in the control (<font color="#006666"><b>SCF_ALL</b></font>)</font></li>
  <li><font face="Tahoma" size="-1">Apply to the text currently in selection (<font color="#006666"><b>SCF_SELECTION</b></font>)</font></li>
  <li><font face="Tahoma" size="-1">Apply to the whole word currently in selection 
    (<font color="#006666"><b>SCF_WORD</b></font> or <font color="#006666"><b>SCF_SELECTION</b></font>)</font></li>
</ol>
<p><font face="Tahoma" size="-1">The first and the second choices are straightforward. 
  The last choice requires a little explanation. If the current selection only 
  covers one or more of the characters in the word but not the whole word, specifying 
  the flag <font color="#006666"><b>SCF_WORD</b></font>+<font color="#006666"><b>SCF_SELECTION</b></font> 
  applies the text formatting to the whole word. Even if there is no current selection, 
  ie, only the caret is positioned in the word, the third choice also applies 
  the text formatting to the whole word.</font></p>
<p><font face="Tahoma" size="-1">To use <font color="#006666"><b>EM_SETCHARFORMAT</b></font>, 
  you need to fill several members of <font color="#006666"><b>CHARFORMAT</b></font> 
  (or <font color="#006666"><b>CHARFORMAT2</b></font>) structure. For example, 
  if we want to set the text color, we will fill the <font color="#006666"><b>CHARFORMAT</b></font> 
  structure as follows:</font></p>
<pre><font face="Tahoma"><b><font color="#000066">.data?
	cf CHARFORMAT &lt;&gt;
....
.code
	mov cf.cbSize,sizeof cf
	mov cf.dwMask,CFM_COLOR
	mov cf.crTextColor,0FF0000h
	invoke SendMessage,hwndRichEdit,EM_SETCHARFORMAT,SCF_ALL,addr cf</font></b></font></pre>
<p><font face="Tahoma" size="-1">The above code snippet sets the text color of 
  the richedit control to pure blue. Note that if there is no text in the richedit 
  control when <font color="#006666"><b>EM_SETCHARFORMAT</b></font> is issued, 
  the text entered into the richedit control following the message will use the 
  text formatting specified by the<font color="#006666"><b> EM_SETCHARFORMAT</b></font> 
  message.<br>
  </font></p>
<h3><font face="Times New Roman, Times, serif" color="#000099">Setting the text/saving 
  the text</font></h3>
<p><font face="Tahoma" size="-1">For those of you who are used to edit control, 
  you'll surely be familiar with <font color="#006666"><b>WM_GETTEXT</b></font>/<font color="#006666"><b>WM_SETTEXT</b></font> 
  as the means to set the text/get the text to/from the control. This method still 
  works with richedit control but may not be efficient if the file is large. Edit 
  control limits the text that can be entered into it to 64K but richedit control 
  can accept text much larger than that. It would be very cumbersome to allocate 
  a very large block of memory (such as 10 MB or so) to receive the text from 
  <font color="#006666"><b>WM_GETTEXT</b></font>. Richedit control offers a new 
  approach to this method, ie. text streaming.</font></p>
<p><font face="Tahoma" size="-1">To put it simply, you provide the address of 
  a callback function to the richedit control. And richedit control will call 
  that callback, passing the address of the buffer to it, when it's ready. The 
  callback will fill the buffer with the data it wants to send to the control 
  or read the data from the buffer and then waits for the next call until the 
  operation is finished. This paradigm is used for both streaming in (setting 
  the text) and streaming out (getting the text out of the control). You'll see 
  that this method is more efficient: the buffer is provided by the richedit control 
  itself so the data are divided into chunks. The operations involve two messages:<font color="#006666"><b> 
  EM_STREAMIN</b></font> and <font color="#006666"><b>EM_STREAMOUT</b></font></font></p>
<p><font face="Tahoma" size="-1">Both <font color="#006666"><b>EM_STREAMIN </b></font>and 
  <font color="#006666"> <b>EM_STREAMOUT</b></font> use the same syntax:</font></p>
<p><font face="Tahoma" size="-1"> <font color="#0000FF"><b>wParam</b></font> == 
  formatting options.</font></p>
<table cellpadding="3" align="center" border="1">
  <tr bgcolor="#FFFFCC"> 
    <td><b><font face="MS Sans Serif" size="-1">SF_RTF</font></b></td>
    <td><font face="MS Sans Serif" size="-1">The data is in the rich-text format 
      (RTF) </font></td>
  </tr>
  <tr bgcolor="#FFFFCC"> 
    <td><b><font face="MS Sans Serif" size="-1">SF_TEXT</font></b></td>
    <td><font face="MS Sans Serif" size="-1">The data is in the plain text format</font></td>
  </tr>
  <tr bgcolor="#FFFFCC"> 
    <td><b><font face="MS Sans Serif" size="-1">SFF_PLAINRTF</font></b></td>
    <td><font face="MS Sans Serif" size="-1">Only the keywords common to all languages 
      are streamed in.</font></td>
  </tr>
  <tr bgcolor="#FFFFCC"> 
    <td><b><font face="MS Sans Serif" size="-1">SFF_SELECTION</font></b></td>
    <td><font face="MS Sans Serif" size="-1">If specified, the target of the operation 
      is the text currently in selection. If you stream the text in, the text 
      replaces the current selection. If you stream the text out, only the text 
      currently in selection is streamed out. If this flag is not specified, the 
      operation affects the whole text in the control.</font></td>
  </tr>
  <tr bgcolor="#FFFFCC"> 
    <td><b><font face="MS Sans Serif" size="-1">SF_UNICODE</font></b></td>
    <td><font face="MS Sans Serif" size="-1">(Available on RichEdit 2.0 or later) 
      Specify the unicode text.</font></td>
  </tr>
</table>
<p><font face="Tahoma" size="-1"> <font color="#0000FF"><b>lParam</b></font> == 
  point to an <font color="#006666"><b>EDITSTREAM</b></font> structure which has 
  the following definition:</font><font face="Tahoma" size="-1"></font></p>
<pre><font face="Tahoma"> <font color="#006666"><b>EDITSTREAM STRUCT 
	dwCookie DWORD    ? 
	dwError DWORD ? 
	pfnCallback DWORD ? 
EDITSTREAM ENDS</b></font></font><font face="Tahoma" size="-1"></font></pre>
<table cellpadding="3" align="center" border="1">
  <tr bgcolor="#FFFFCC"> 
    <td><b><font face="MS Sans Serif" size="-1">dwCookie</font></b></td>
    <td><font face="MS Sans Serif" size="-1">application-defined value that will 
      be passed to the callback function speficied in <font color="#000066"><b>pfnCallback</b></font> 
      member below. We normally pass some important value to the callback function 
      such as the file handle to use in the stream-in/out procedure.</font></td>
  </tr>
  <tr bgcolor="#FFFFCC"> 
    <td><b><font face="MS Sans Serif" size="-1">dwError</font></b></td>
    <td><font face="MS Sans Serif" size="-1">Indicates the results of the stream-in 
      (read) or stream-out (write) operation. A value of zero indicates no error. 
      A nonzero value can be the return value of the EditStreamCallback function 
      or a code indicating that the control encountered an error. </font></td>
  </tr>
  <tr bgcolor="#FFFFCC"> 
    <td><b><font face="MS Sans Serif" size="-1">pfnCallback</font></b></td>
    <td><font face="MS Sans Serif" size="-1">Pointer to an EditStreamCallback 
      function, which is an application-defined function that the control calls 
      to transfer data. The control calls the callback function repeatedly, transferring 
      a portion of the data with each call</font></td>
  </tr>
</table>
<p><font face="Tahoma" size="-1">The editstream callback function has the following 
  definition:</font></p>
<pre><font face="Tahoma">	<b><font color="#990099">EditStreamCallback</font> proto <font color="#CC00CC">dwCookie</font>:DWORD,<br>				 <font color="#CC00CC">pBuffer</font>:DWORD,
				 <font color="#CC00CC">NumBytes</font>:DWORD,
				 <font color="#CC00CC">pBytesTransferred</font>:DWORD</b></font></pre>
<p><font face="Tahoma" size="-1">You have to create a function with the above 
  prototype in your program. And then pass its address to <font color="#006666"><b>EM_STREAMIN</b></font> 
  or <font color="#006666"><b>EM_STREAMOUT</b></font> via <font color="#006666"><b>EDITSTREAM</b></font> 
  structure.</font></p>
<p><font face="Tahoma" size="-1">For stream-in operation (settting the text in 
  the richedit control)</font><font face="Tahoma">:</font></p>
<pre><font face="Tahoma">	<font color="#660066"><b><font color="#990099">dwCookie</font></b></font>: the application-defined value you pass to <font color="#006666"><b>EM_STREAMIN</b></font> via <font color="#006666"><b>EDITSTREAM</b></font> structure. We almost always 
		pass the file handle of the file we want to set its content to the control here.</font><font face="Tahoma">
	<font color="#990099"><b>pBuffer</b></font>: points to the buffer provided by the richedit control that will receive the text from your callback function.
	<font color="#990099"><b>NumBytes</b></font>: the maximum number of bytes you can write the the buffer (pBuffer) in this call. You <font color="#000099"><b>MUST</b></font> always obey this limit, ie, you can send
		less data than the value in NumBytes but must not send more data than this value. You can think of this value as the size
		of the buffer in pBuffer.
   <b><font color="#990099">pBytesTransferred</font></b>: points to a dword that you must set the value indicating the number of bytes you actually transferred to the buffer.
		This value is usually identical to the value in <font color="#990099"><b>NumBytes</b></font>. The exception is when the data is to send is less than
		the size of the buffer provided such as when the end of file is reached.</font></pre>
<p><font face="Tahoma"><font size="-1"> For stream-out operation (getting the 
  text out of the richedit control):</font></font><font face="Tahoma"><font size="-1"></font></font><font face="Tahoma"><font size="-1"></font></font></p>
<pre><font face="Tahoma">	<font color="#FFFFFF"><b><font color="#990099">dwCookie</font></b></font>: Same as the stream-in operation. We usually pass the file handle we want to write the data to in this parameter. 
	<font color="#990099"><b>pBuffer</b></font>: points to the buffer provided by the richedit control that is filled with the data from the richedit control. 
		To obtain its size, you must examine the value of <font color="#990099"><b>NumBytes</b></font>. <font color="#990099"><b>
	NumBytes</b></font>: the size of the data in the buffer pointed to by pBuffer. 
	<font color="#990099"><b>pBytesTransferred</b></font>: points to a dword that you must set the value indicating the number of bytes you actually read from the buffer.</font><font face="Tahoma"><font size="-1"></font></font></pre>
<p><font face="Tahoma" size="-1">The callback function returns 0 to indicate success 
  and richedit control will continue calling the callback function if there is 
  still data left to read/write. If some error occurs during the process and you 
  want to stop the operation, returns a non-zero value and the richedit control 
  will discard the data pointed to by pBuffer. The error/success value will be 
  filled in the <font color="#006666"><b>dwError</b></font> field of <font color="#990000"><b>EDITSTREAM</b></font> 
  so you can examine the error/success status of the stream operation after <font color="#006666"><b>SendMessage</b></font> 
  returns. </font><font face="Tahoma"><font size="-1"></font></font></p>
<h3><font face="Times New Roman, Times, serif" color="#0000CC">Example:</font></h3>
<p><font face="Tahoma" size="-1">The example below is a simple editor which you 
  can open an asm source code file, edit and save it. It uses RichEdit control 
  version 2.0 or above.</font></p>
<pre align="left"><b><font face="Tahoma">.386
.model flat,stdcall
option casemap:none
include \masm32\include\windows.inc
include \masm32\include\user32.inc
include \masm32\include\comdlg32.inc
include \masm32\include\gdi32.inc
include \masm32\include\kernel32.inc
includelib \masm32\lib\gdi32.lib
includelib \masm32\lib\comdlg32.lib
includelib \masm32\lib\user32.lib
includelib \masm32\lib\kernel32.lib

WinMain proto :DWORD,:DWORD,:DWORD,:DWORD

.const
IDR_MAINMENU                   equ 101
IDM_OPEN                      equ  40001
IDM_SAVE                       equ 40002
IDM_CLOSE                      equ 40003
IDM_SAVEAS                     equ 40004
IDM_EXIT                       equ 40005
IDM_COPY                      equ  40006
IDM_CUT                       equ  40007
IDM_PASTE                      equ 40008
IDM_DELETE                     equ 40009
IDM_SELECTALL                  equ 40010
IDM_OPTION 			equ 40011
IDM_UNDO			equ 40012
IDM_REDO			equ 40013
IDD_OPTIONDLG                  equ 101
IDC_BACKCOLORBOX               equ 1000
IDC_TEXTCOLORBOX               equ 1001

RichEditID 			equ 300

.data
ClassName db "<font color="#0000FF">IczEditClass</font>",0
AppName  db "<font color="#0000FF">IczEdit version 1.0</font>",0
RichEditDLL db "<font color="#0000FF">riched20.dll</font>",0
RichEditClass db "<font color="#0000FF">RichEdit20A</font>",0
NoRichEdit db "<font color="#0000FF">Cannot find riched20.dll</font>",0
ASMFilterString 		db "<font color="#0000FF">ASM Source code (*.asm)</font>",0,"*<font color="#0000FF">.asm</font>",0
				db "<font color="#0000FF">All Files (*.*)</font>",0,"<font color="#0000FF">*.*</font>",0,0
OpenFileFail db "<font color="#0000FF">Cannot open the file</font>",0
WannaSave db "<font color="#0000FF">The data in the control is modified. Want to save it?</font>",0
FileOpened dd FALSE
BackgroundColor dd 0FFFFFFh		<font color="#006666">; default to white</font>
TextColor dd 0		<font color="#006666">; default to black</font>

.data?
hInstance dd ?
hRichEdit dd ?
hwndRichEdit dd ?
FileName db 256 dup(?)
AlternateFileName db 256 dup(?)
CustomColors dd 16 dup(?)

.code
start:
	invoke GetModuleHandle, NULL
	mov    hInstance,eax
<font color="#FF0033">	invoke LoadLibrary,addr RichEditDLL</font>
	.if eax!=0
		mov hRichEdit,eax
		invoke WinMain, hInstance,0,0, SW_SHOWDEFAULT
		invoke FreeLibrary,hRichEdit
	.else
		invoke MessageBox,0,addr NoRichEdit,addr AppName,MB_OK or MB_ICONERROR
	.endif
	invoke ExitProcess,eax
	
WinMain proc hInst:DWORD,hPrevInst:DWORD,CmdLine:DWORD,CmdShow:DWORD
	LOCAL wc:WNDCLASSEX
	LOCAL msg:MSG
	LOCAL hwnd:DWORD
	mov   wc.cbSize,SIZEOF WNDCLASSEX
	mov   wc.style, CS_HREDRAW or CS_VREDRAW
	mov   wc.lpfnWndProc, OFFSET WndProc
	mov   wc.cbClsExtra,NULL
	mov   wc.cbWndExtra,NULL
	push  hInst
	pop   wc.hInstance
	mov   wc.hbrBackground,COLOR_WINDOW+1
	mov   wc.lpszMenuName,IDR_MAINMENU
	mov   wc.lpszClassName,OFFSET ClassName
	invoke LoadIcon,NULL,IDI_APPLICATION
	mov   wc.hIcon,eax
	mov   wc.hIconSm,eax
	invoke LoadCursor,NULL,IDC_ARROW
	mov   wc.hCursor,eax
	invoke RegisterClassEx, addr wc
	INVOKE CreateWindowEx,NULL,ADDR ClassName,ADDR AppName,\
           WS_OVERLAPPEDWINDOW,CW_USEDEFAULT,\
           CW_USEDEFAULT,CW_USEDEFAULT,CW_USEDEFAULT,NULL,NULL,\
           hInst,NULL
	mov   hwnd,eax
	invoke ShowWindow, hwnd,SW_SHOWNORMAL
	invoke UpdateWindow, hwnd
	.while TRUE
		invoke GetMessage, ADDR msg,0,0,0
		.break .if (!eax)
		invoke TranslateMessage, ADDR msg
		invoke DispatchMessage, ADDR msg
	.endw
	mov   eax,msg.wParam
	ret
WinMain endp

<font color="#003399">StreamInProc</font> proc hFile:DWORD,pBuffer:DWORD, NumBytes:DWORD, pBytesRead:DWORD
	invoke ReadFile,hFile,pBuffer,NumBytes,pBytesRead,0
	xor eax,1
	ret
<font color="#003399">StreamInProc</font> endp