下面的函数将返回控件的文本行数,如果控件的文本为空也会返回1。 Function GetLineCount(CTextBox
As TextBox) As Long GetLineCount = SendMessage(CTextBox.hWnd,
EM_GETLINECOUNT, 0, 0) End Function
下面的函数将返回控件中显示的第一行的行号。
Function GetFirstVisableLine(CTextBox As TextBox) As Long
GetFirstVisableLine = SendMessageBynum(CTextBox.hwnd,
EM_GETFIRSTVISIBLELINE, 0, 0) End Function
下面的函数将返回控件能显示的行数。
Function GetVisibleLines(CTextBox As TextBox) As Long Dim rc As RECT
Dim hDC&, lfont&, oldfont& Dim di&, lc& Dim
tm As TEXTMETRIC lc = SendMessage(CTextBox.hwnd, EM_GETRECT, 0, rc)
lfont = SendMessage(CTextBox.hwnd, WM_GETFONT, 0, 0) hDC =
GetDC(CTextBox.hwnd) If lfont $#@60;$#@62; 0 Then oldfont =
SelectObject(hDC, lfont) di = GetTextMetrics(hDC, tm) If lfont
$#@60;$#@62; 0 Then lfont = SelectObject(hDC, oldfont) GetVisibleLines =
(rc.bottom - rc.top) / tm.tmHeight di = ReleaseDC(CTextBox.hwnd, hDC)
End Function
下面的函数能够滚动控件,不过在滚动之前最好判断控件的文本行数和能够显示的行数,以免滚动时发生混乱。函数SendMessageBynum是一个SendMessage函数的安全声明函数,其定义与SendMessage函数完全相同,只是函数名不同。
Function ScrollTextBox(CTextBox As TextBox, nVal As Long, _ Optional
nVertical As Boolean = True) As Long If nVertical Then ScrollTextBox
= SendMessageBynum(CTextBox.hwnd, EM_LINESCROLL, 0, nVal) Else
ScrollTextBox = SendMessageBynum(CTextBox.hwnd, EM_LINESCROLL, nVal, 0)
End If End Function
下面的函数能够返回控件指定行的文本。SendMessageBystring与SendMessageBynum类似。 Function
GetLineText(CTextBox As TextBox, LineIndex As Long) As String Dim lc&,
linechar& linechar = SendMessageBynum(CTextBox.hwnd, EM_LINEINDEX,
LineIndex, 0) lc = SendMessageBynum(CTextBox.hwnd, EM_LINELENGTH, linechar,
0) + 1 GetLineText = String$(lc + 2, 0) Mid$(GetLineText, 1, 1) =
Chr(lc And &HFF) Mid$(GetLineText, 2, 1) = Chr(lc \ &H100) lc
= SendMessageBystring(CTextBox.hwnd, EM_GETLINE, LineIndex, GetLineText)
GetLineText = left(GetLineText, lc) End Function 下面的函数可以设置控件的左边距。
Public Const EM_SETMARGINS& = &HD3 Public Const
EC_LEFTMARGIN& = &H1 Function SetMargins(CTextBox As TextBox, nVal
As Long) As Long SetMargins = SendMessageBynum(CTextBox.hwnd,
EM_SETMARGINS, EC_LEFTMARGIN, nVal) End Function
没有相关教程