怎样才能知道TextBox中有多少行了？

[xingming_sun]

我做了一个关于自动处理方面的小程序，用TextBox控件来显示程序运行过程
中出现的种种提示信息。我担心TextBox不能显示太多的内容，因而打算
在TextBox显示50行的时候清空TextBox,但是如何才能得知TextBox已经
有50行了呢？拜托各位了，谢谢。

或则有其它的解决方法，烦请告知，不胜感激。

[cloud_soft]

sendmessage, 晚了

[tipstudio_zsp]

有一个不用api的办法
你查找一下字符串里面有多少个换行符即可

[dapha]

有一个笨方法就是查找vbcrlf，方法可行如果数据多的话速度较慢

[leonkim]

你可以先算一算TextBox中每行多少个字符，再＊50，当LEN(TEXT1)大于这个值时，text1=""
就可以了，最好要区分一个中英文字符。

[DeityFox]

在TextBox中如何得知所有的行数

原始来源:cww

呼叫方式

Dim LineCnt as Long

LineCnt = TextBoxLineCnt(Text1)


Declare Function SendMessage Lib "user32" Alias "SendMessageA" _
(ByVal hwnd As Long, ByVal wMsg As Long, ByVal wParam As Long, _
lParam As Any) As Long
Public Const EM_GETLINECOUNT = &HBA

Public Function TextBoxLineCnt(ctl As TextBox) As Long
TextBoxLineCnt = SendMessage(ctl.hwnd, EM_GETLINECOUNT, 0, 0)
End Function

[DeityFox]

在TextBox中如何得知Caret所在位置

原始来源:cww

'在form中放一个textBox两个label
Const EM_GETSEL = &HB0
Const EM_LINEFROMCHAR = &HC9
Const EM_LINEINDEX = &HBB

Private Declare Function SendMessage Lib "user32" Alias "SendMessageA" _
(ByVal hwnd As Long, ByVal wMsg As Long, ByVal wParam As Long, _
lParam As Any) As Long

Public Sub GetCaretPos(ByVal hwnd5 As Long, LineNo As Long, ColNo As Long)
Dim i As Long, j As Long
Dim lParam As Long, wParam As Long
Dim k As Long
i = SendMessage(hwnd5, EM_GETSEL, wParam, lParam)
j = i / 2 ^ 16 '取得目前Caret所在前面有多少个byte
LineNo = SendMessage(hwnd5, EM_LINEFROMCHAR, j, 0) '取得前面有多少行
LineNo = LineNo + 1
k = SendMessage(hwnd5, EM_LINEINDEX, -1, 0)
'取得目前caret所在行前面有多少个byte
ColNo = j - k + 1
End Sub

Private Sub Form_Load()
Dim LineNo As Long, ColNo As Long

Call GetCaretPos(Text1.hwnd, LineNo, ColNo)
Label1.Caption = LineNo
Label2.Caption = ColNo

End Sub

Private Sub Text1_KeyUp(KeyCode As Integer, Shift As Integer)
Dim LineNo As Long, ColNo As Long

Call GetCaretPos(Text1.hwnd, LineNo, ColNo)
Label1.Caption = LineNo
Label2.Caption = ColNo

End Sub

Private Sub Text1_MouseDown(Button As Integer, Shift As Integer, X As Single, Y As Single)
Dim LineNo As Long, ColNo As Long

Call GetCaretPos(Text1.hwnd, LineNo, ColNo)
Label1.Caption = LineNo
Label2.Caption = ColNo

End Sub

[yangzhaoyu]

Private Sub Command1_Click()
Dim txtLine As Long
txtLine = SendMessage(Text1.hwnd, EM_GETLINECOUNT, 0, ByVal 0&)
Debug.Print txtLine
End Sub