自学教程：C++ GetTextLength函数代码示例

bool GUI_TextField::HandleEvent(const char *action){    if (!strcmp(action, "accept")) {        GUI_Page *page = GetPage();        if (page) {            page->UpdateFocusWidget(1);            page->DecRef();        }        return true;    } else    if (!strcmp(action, "prev")) {        SetCursorPos(GetCursorPos() - 1);        InputDigit(-1);        return true;    } else    if (!strcmp(action, "next")) {        SetCursorPos(GetCursorPos() + 1);        InputDigit(-1);        return true;    } else    if ((GetFlags() & WIDGET_FOCUSED &&         (!strcmp(action, "stop") ||          !strcmp(action, "cancel"))) ||        !strcmp(action, "clear") ||        !strcmp(action, "backspace")) {        Backspace();        InputDigit(-1);        return true;    } else    if (!strcmp(action, "delete")) {        DeleteCurrChar();        InputDigit(-1);        return true;    } else    if (!strcmp(action, "home") ||        !strcmp(action, "first")) {        SetCursorPos(0);        InputDigit(-1);        return true;    } else    if (!strcmp(action, "end") ||        !strcmp(action, "last")) {        SetCursorPos(GetTextLength());        InputDigit(-1);        return true;    } else    if (!strncmp(action, "key", 3) &&        strlen(action) == 4) {        SendChar(action[3], true);        InputDigit(-1);        return true;    } else    if (!strncmp(action, "number", 6) &&        strlen(action) == 7 &&        isdigit(action[6])) {        InputDigit(atoi(action + 6));        return true;    }    return GUI_Widget::HandleEvent(action);}

	//----------------------------------------------------------------------------	void Write(Real x, Real y, Real z, unsigned int color,		const char *text, int count, FONT_ALIGN mode)	{		if (!mInitialized)			return;		auto& renderer = Renderer::GetInstance();		if (renderer.GetRendererOptions()->r_noText)			return;		//		if (count < 0)			count = GetTextLength(text);		if (mode == FONT_ALIGN_CENTER)		{			Real w = GetTextWidth(text, count);			x -= w / 2;		}		else if (mode == FONT_ALIGN_RIGHT)		{			Real w = GetTextWidth(text, count);			x -= w;		}		mColor = color;		renderer.UpdateObjectConstantsBuffer(&mObjectConstants);		InternalWrite(Round(x), Round(y), z, text, count);	}

/*================CSyntaxRichEditCtrl::BracedSectionEnd================*/bool CSyntaxRichEditCtrl::BracedSectionEnd(char braceStartChar, char braceEndChar){	long selStart, selEnd;	int brace, i;	idStr text;	GetSel(selStart, selEnd);	GetText(text, 0, GetTextLength());	for (brace = 1, i = Min(selStart-2, (long)text.Length()-1); i >= 0; i--) {		if (text[i] == braceStartChar) {			brace--;			if (brace == 0) {				break;			}		} else if (text[i] == braceEndChar) {			brace++;		}	}	if (brace == 0) {		bracedSection[0] = i;		bracedSection[1] = selStart - 1;		BracedSectionAdjustEndTabs();		BracedSectionShow();	}	return (brace == 0);}

void Key_GetWord(uint8 KeyValue,char *D,uint8 InType){  uint8 Index,Length;	char CodeBuf[200],*Data=D;	BufferFill(&CodeBuf[0],0,sizeof(CodeBuf));	if(InType&IT_Dot)StringEndingAppend(".",&CodeBuf[0]);	if(InType&IT_Minus)StringEndingAppend("-",&CodeBuf[0]);	if(InType&IT_Num)StringEndingAppend("0123456789",&CodeBuf[0]);	if(InType&IT_ASCIIS)StringEndingAppend("abcdefghijklmnopqrstuvwxyz",&CodeBuf[0]);	if(InType&IT_ASCIIB)StringEndingAppend("ABCDEFGHIJKLMNOPQRSTUVWXYZ",&CodeBuf[0]);	if(InType&IT_CurCLiB)StringEndingAppend((void *)(Tos_GetFontHandle()->P_CIndex),&CodeBuf[0]);	Length=GetTextLength(&CodeBuf[0]);	Length++;	Index=Index_Word(CodeBuf,Data,Length);	if(Index==0xff)Index=0;	 if(KeyValue==Key_Up)   {		  if(CodeBuf[Index]<0x80)Index++;else Index+=2;if(Index>=Length)Index=0;       if(CodeBuf[Index]<0x80){*Data=CodeBuf[Index];}else {*(uint16 *)Data=*(uint16 *)&CodeBuf[Index];}	 }	  if(KeyValue==Key_Down)   {		   if(CodeBuf[Index-2]<0x80)Index--;else Index-=2;if(Index==0xff)Index=(Length);       if(CodeBuf[Index]<0x80){*Data=CodeBuf[Index];}else {*(uint16 *)Data=*(uint16 *)&CodeBuf[Index];} 	 }	 Index=Index_Word(CodeBuf,Data,Length);	 if(Index==0xff)Index=0;}

void Key_GetASCII(uint8 KeyValue,uint8 *Data,uint8 InType){  uint8 Index,Length;	char CodeBuf[200];	BufferFill(&CodeBuf[0],0,sizeof(CodeBuf));	if(InType&IT_Dot)StringEndingAppend(".",&CodeBuf[0]);	if(InType&IT_Minus)StringEndingAppend("-",&CodeBuf[0]);	if(InType&IT_Num)StringEndingAppend("0123456789",&CodeBuf[0]);	if(InType&IT_ASCIIS)StringEndingAppend("abcdefghijklmnopqrstuvwxyz",&CodeBuf[0]);	if(InType&IT_ASCIIB)StringEndingAppend("ABCDEFGHIJKLMNOPQRSTUVWXYZ",&CodeBuf[0]);	if(InType&IT_CurCLiB)StringEndingAppend((void *)(Tos_GetFontHandle()->P_CIndex),&CodeBuf[0]);	if(InType&IT_End)StringEndingAppend("/r/n",&CodeBuf[0]);	StringEndingAppend("/n",&CodeBuf[0]);	Length=GetTextLength(&CodeBuf[0]);   if(KeyValue==Key_Up)   {       Index=Index_Uchar(CodeBuf,*Data);				Index++;       if(Index>=(Length-1))Index=0;              *Data=CodeBuf[Index];	 }	  if(KeyValue==Key_Down)   {       Index=Index_Uchar(CodeBuf,*Data);		   if(Index==0)Index=(Length-1);       Index--;       *Data=CodeBuf[Index];	 }}

/*================CSyntaxRichEditCtrl::GetNameForMousePosition================*/bool CSyntaxRichEditCtrl::GetNameForMousePosition(idStr &name) const{	int charIndex, startCharIndex, endCharIndex, type;	idStr text;	charIndex = CharFromPos(mousePoint);	for (startCharIndex = charIndex; startCharIndex > 0; startCharIndex--) {		GetText(text, startCharIndex - 1, startCharIndex);		type = charType[text[0]];		if (type != CT_NAME && type != CT_NUMBER) {			break;		}	}	for (endCharIndex = charIndex; endCharIndex < GetTextLength(); endCharIndex++) {		GetText(text, endCharIndex, endCharIndex + 1);		type = charType[text[0]];		if (type != CT_NAME && type != CT_NUMBER) {			break;		}	}	GetText(name, startCharIndex, endCharIndex);	return (endCharIndex > startCharIndex);}

LONG CRchTxtPtr::GetCchLeftRunPF() {	TRACEBEGIN(TRCSUBSYSBACK, TRCSCOPEINTERN, "CRchTxtPtr::GetCchLeftRunPF");	return _rpPF.IsValid()		? _rpPF.GetCchLeft() : GetTextLength() - GetCp();}

void GUITextBox::OnKeyDown(UCHAR key){	SetShift(keys[VK_SHIFT]);	if(GetText())	{		if((IsAlpabetic(key) || key == VK_SPACE) &&			GetTextLength() < GetMaxTextLength())		{			char* new_text = new char[strlen(GetText())+2];			if(GetShift())				sprintf(new_text, "%s%c/0", GetText(), key);			else				sprintf(new_text, "%s%c/0", GetText(), tolower(key));			try			{				delete[] GetText();			}			catch(...)			{				WriteToLog("Exception in GUITextBox::OnKeyDown()");			}			SetText(new_text);			SetTextLength(strlen(GetText()));		}		else if(key == VK_BACK)		{			UINT len = strlen(GetText());			if(len > 0)			{				string s = string(GetText());				char* new_text = new char[len];				sprintf(new_text, "%s/0", s.substr(0, s.length()-1).c_str());								try				{					delete[] GetText();				}				catch(...)				{					WriteToLog("Exception in GUITextBox::OnKeyDown()");				}				SetText(new_text);				SetTextLength(strlen(GetText()));			}		}	}	else	{		char* new_text = new char[1];		if(GetShift())			new_text[0] = key;		else			new_text[0] = tolower(key);		SetText(new_text);	}}

void CTextEditor::Render(HDC hdc, const LOGFONT *plf){    HFONT hFont = CreateFontIndirect(plf);    if (hFont)    {        HFONT hFontOrg = (HFONT)SelectObject(hdc, hFont);        _layout.Layout(hdc, GetTextBuffer(), GetTextLength());        _layout.Render(hdc, GetTextBuffer(), GetTextLength(), _nSelStart, _nSelEnd,                       _nCompStart, _nCompEnd,                       _prgAttr, _lAttr, _prgClauseInfo, _lClauseInfo);        SelectObject(hdc, hFontOrg);        DeleteObject(hFont);    }}

/*******************************************************************************Func:菜单项回传Date:2016-3-25Note:*******************************************************************************/uint8 COM_Menu_Load(uint8 Index,uint8 *Menu){	uint8 Length;	if(Index>=Menu_OptionLength(MenuList))return 0;	MUI_GetOptionString((char *)Menu,&MenuList[Index]);	Length=GetTextLength(Menu);	return Length;}

int GUI_TextField::OnGotFocus(void){    if (!GUI_Widget::OnGotFocus()) {        return 0;    }    SetCursorPos(GetTextLength());    return 1;}

NS_IMETHODIMPHTMLTextAreaElement::GetTextLength(int32_t *aTextLength){  NS_ENSURE_ARG_POINTER(aTextLength);  *aTextLength = GetTextLength();  return NS_OK;}

bool wxTextDataObject::GetDataHere(void *buf) const{    // NOTE: use wxTmemcpy() instead of wxStrncpy() to allow    //       retrieval of strings with embedded NULLs    wxTmemcpy( (wxChar*)buf, GetText().c_str(), GetTextLength() );    return true;}

//右键消息VOID CRichEditTrace::OnRButtonDown(UINT nFlags, CPoint point){	CMenu menu;	ClientToScreen(&point);	menu.CreatePopupMenu();	CHARRANGE sl;	GetSel(sl);	menu.AppendMenu(MF_STRING | (sl.cpMax != sl.cpMin) ? 0 : MF_DISABLED | MF_GRAYED, IDM_MENU0, "复制(&C)/tCtrl+C");	menu.AppendMenu(MF_STRING | (GetTextLength() > 0 && sl.cpMax - sl.cpMin < GetTextLength()) ? 0 : MF_DISABLED | MF_GRAYED, IDM_MENU1, "全选(&A)/tCtrl+A");	menu.AppendMenu(MF_STRING | (false) ? 0 : MF_DISABLED | MF_GRAYED, IDM_MENU2, "删除(&D)");	menu.AppendMenu(MF_STRING | (GetTextLength() > 0) ? 0 : MF_DISABLED | MF_GRAYED, IDM_MENU3, "清除信息");	menu.AppendMenu(MF_SEPARATOR, 0);	menu.AppendMenu(MF_STRING | (GetTextLength() > 0) ? 0 : MF_DISABLED | MF_GRAYED, IDM_MENU4, "保存信息...");	TrackPopupMenu(menu.m_hMenu, nFlags, point.x, point.y, 0, m_hWnd, NULL);}

int SciEdit::GetText(LPTSTR szText){	if (szText == NULL)		return 0;	*szText = '/0';	long lLen = GetTextLength();	Call(SCI_GETTEXT, lLen+1, (LPARAM)szText);	return lLen;}

bool SearchableEditor::find(bool newSearch){    if (!fd)        fd = new FindDialog(this, ::wxGetTopLevelParent(this));    if (newSearch || findTextM.empty())    {        if (newSearch)        {            // find selected text            wxString findText(GetSelectedText());            // failing that initialize with the word at the caret            if (findText.empty())            {                int pos = GetCurrentPos();                int start = WordStartPosition(pos, true);                int end = WordEndPosition(pos, true);                if (end > start)                    findText = GetTextRange(start, end);            }            fd->SetFindText(findText);        }        // do not re-center dialog if it is already visible        if (!fd->IsShown())            fd->Show();        fd->SetFocus();        return false;    // <- caller shouldn't care about this    }    int start = GetSelectionEnd();    if (findFlagsM.has(se::FROM_TOP))    {        start = 0;        findFlagsM.remove(se::ALERT);    // remove flag after first find    }    int end = GetTextLength();    int p = FindText(start, end, findTextM, findFlagsM.asStc());    if (p == -1)    {        if (findFlagsM.has(se::WRAP))            p = FindText(0, end, findTextM, findFlagsM.asStc());        if (p == -1)        {            if (findFlagsM.has(se::ALERT))                wxMessageBox(_("No more matches"), _("Search complete"), wxICON_INFORMATION|wxOK);            return false;        }    }    centerCaret(true);    GotoPos(p);    GotoPos(p + findTextM.Length());    SetSelectionStart(p);    SetSelectionEnd(p + findTextM.Length());    centerCaret(false);    return true;}

/* *	CTxtEdit::GetClipboardData * *	@mfunc	return an data transfer object for the indicated *	range * *	@rdesc *		HRESULT				Success code. */STDMETHODIMP CTxtEdit::GetClipboardData( 	CHARRANGE *lpchrg, 			//@parm the range of text to use	DWORD reco,					//@parm operation the data is for	LPDATAOBJECT *lplpdataobj)	//@parm where to put the data object{	TRACEBEGIN(TRCSUBSYSOLE, TRCSCOPEEXTERN, "CTxtEdit::GetClipboardData");	CCallMgr callmgr(this);	HRESULT hr;	LONG cpMin, cpMost;	CLightDTEngine * pldte = GetDTE();	//Make sure cpMin and cpMost are within the current text limits.	//Interpret neg. value for cpMin as the beginning of the text,	//and neg. value for cpMax as the end of the text.  If a char range	//is not given use the current selection.	if(lpchrg)	{		LONG cchText;		cchText = (LONG)GetTextLength();		cpMin = max(0, lpchrg->cpMin);		cpMin = min(cchText, lpchrg->cpMin);		cpMost = lpchrg->cpMost;		if(lpchrg->cpMost < 0 || lpchrg->cpMost > cchText)			cpMost = cchText;	}	else	{		CTxtSelection * psel = GetSel();		psel->GetRange(cpMin, cpMost);	}	//Make sure this is a valid range.	if(cpMin >= cpMost)	{		*lplpdataobj = NULL;		return cpMin == cpMost					? NOERROR					: ResultFromScode(E_INVALIDARG);	}	CTxtRange rg(this, cpMin, cpMin-cpMost);	//We don't use reco for anything.	hr = pldte->RangeToDataObject(&rg, SF_RTF, lplpdataobj);#ifdef DEBUG	if(hr != NOERROR)		TRACEERRSZSC("GetClipboardData", E_OUTOFMEMORY);#endif	return hr;}

void DaCai_TextBox(uint16 ScreenID,uint16 ControlID,char *fmt,...){  va_list ap;	char String[256];	va_start(ap,fmt);	vsprintf(String,fmt,ap);	DaCai_SetTextBox(ScreenID,ControlID,(uint8 *)String,GetTextLength(String));	va_end(ap);	}

void DaCai_Printf(char *fmt,...){  va_list ap;	char String[256];	va_start(ap,fmt);	vsprintf(String,fmt,ap);	DaCai_SetTextBox(0x00,0x11,(uint8 *)String,GetTextLength(String));	va_end(ap);	}

void CTextEditor::MoveSelectionNext(){    UINT nTextLength = GetTextLength();    if (_nSelEnd < nTextLength)       _nSelEnd++;    _nSelStart = _nSelEnd;    _pTextStore->OnSelectionChange();}

void CFulEditCtrl::ScrollToEnd() {	SetRedraw(FALSE);	SetSel(0, 0);	ScrollCaret();	int l = GetTextLength();	SetSel(l, l);	SendMessage(EM_SCROLLCARET, 0, 0);	SetRedraw(TRUE);	Invalidate();}

	//----------------------------------------------------------------------------	Real GetTextWidth(const char *text, int count = -1, Real *outMinY = 0, Real *outMaxY = 0)	{		if (count < 0)			count = GetTextLength(text);		Real x = 0;		Real minY = 10000;		Real maxY = -10000;		for (int n = 0; n < count;)		{			TextTags::Enum tag;			int imgLen;			int skiplen = SkipTags(&text[n], &tag, &imgLen);			if (skiplen>0)			{				if (tag == TextTags::Img)				{					x += imgLen;				}				do				{					n += skiplen;					skiplen = SkipTags(&text[n], &tag, &imgLen);					if (tag == TextTags::Img)					{						x += imgLen;					}				} while (skiplen > 0);			}			if (n >= count)				break;			int charId = GetTextChar(text, n, &n);			SCharDescr *ch = GetChar(charId);			if (ch == 0) ch = &mDefChar;			x += mScale * (ch->xAdv);			Real h = mScale * Real(ch->srcH);			Real y = mScale * (Real(mBase) - Real(ch->yOff));			if (minY > y - h)				minY = y - h;			if (maxY < y)				maxY = y;			if (n < count)				x += AdjustForKerningPairs(charId, GetTextChar(text, n));		}		if (outMinY) *outMinY = minY;		if (outMaxY) *outMaxY = maxY;		return x;	}

 void NativeTextfieldWin::OnMouseMove(UINT keys, const gfx::Point& point) {     SetContainsMouse(true);     // Clamp the selection to the visible text so the user can't drag to select     // the "phantom newline".  In theory we could achieve this by clipping the X     // coordinate, but in practice the edit seems to behave nondeterministically     // with similar sequences of clipped input coordinates fed to it.  Maybe it's     // reading the mouse cursor position directly?     //     // This solution has a minor visual flaw, however: if there's a visible     // cursor at the edge of the text (only true when there's no selection),     // dragging the mouse around outside that edge repaints the cursor on every     // WM_MOUSEMOVE instead of allowing it to blink normally.  To fix this, we     // special-case this exact case and discard the WM_MOUSEMOVE messages instead     // of passing them along.     //     // But even this solution has a flaw!  (Argh.)  In the case where the user     // has a selection that starts at the edge of the edit, and proceeds to the     // middle of the edit, and the user is dragging back past the start edge to     // remove the selection, there's a redraw problem where the change between     // having the last few bits of text still selected and having nothing     // selected can be slow to repaint (which feels noticeably strange).  This     // occurs if you only let the edit receive a single WM_MOUSEMOVE past the     // edge of the text.  I think on each WM_MOUSEMOVE the edit is repainting its     // previous state, then updating its internal variables to the new state but     // not repainting.  To fix this, we allow one more WM_MOUSEMOVE through after     // the selection has supposedly been shrunk to nothing; this makes the edit     // redraw the selection quickly so it feels smooth.     CHARRANGE selection;     GetSel(selection);     const bool possibly_can_discard_mousemove =         (selection.cpMin==selection.cpMax) &&         (((selection.cpMin==0) &&         (ClipXCoordToVisibleText(point.x(), false)>point.x())) ||         ((selection.cpMin==GetTextLength()) &&         (ClipXCoordToVisibleText(point.x(), false)<point.x())));     if(!can_discard_mousemove_ || !possibly_can_discard_mousemove)     {         can_discard_mousemove_ = possibly_can_discard_mousemove;         ScopedFreeze freeze(this, GetTextObjectModel());         OnBeforePossibleChange();         // Force the Y coordinate to the center of the clip rect.  The edit         // behaves strangely when the cursor is dragged vertically: if the cursor         // is in the middle of the text, drags inside the clip rect do nothing,         // and drags outside the clip rect act as if the cursor jumped to the         // left edge of the text.  When the cursor is at the right edge, drags of         // just a few pixels vertically end up selecting the "phantom newline"...         // sometimes.         RECT r;         GetRect(&r);         DefWindowProc(WM_MOUSEMOVE, keys, MAKELPARAM(point.x(), (r.bottom-r.top)/2));         OnAfterPossibleChange(true);     } }

void CTextEditor::MoveSelectionNext(){    UINT nTextLength = GetTextLength();    if (_nSelEnd < nTextLength)       _nSelEnd++;    _nSelStart = _nSelEnd;    SetCompositionForm();    FlushCompositionString();}

HRESULT touchmind::control::DWriteEditControlTextStoreACP::MoveACPToEnd() {  if (_IsLocked(TS_LF_READ)) {    return S_OK;  }  _LockDocument(TS_LF_READWRITE);  LONG textLength = static_cast<LONG>(GetTextLength());  HRESULT hr = ChangeACPWithoutLock(textLength, textLength, TS_AE_START);  _UnlockDocument();  m_AdviseSink.pTextStoreACPSink->OnLayoutChange(TS_LC_CHANGE, EDIT_VIEW_COOKIE);  return hr;}