Counting lines in a multi-line textbox

Often, you may need to know how many lines of text there are in a multi-line textbox. While Visual Basic makes it easy to determine how many paragraphs the textbox contains, using code like so:

Private Sub Command1_Click()
    Dim myParas As Variant
    myParas = Split(Text1, vbNewLine)
    MsgBox UBound(myParas) + 1
End Sub


This code, as you can see, only parses out hard carriage returns; whereas you want to know how many lines of text the control contains.

To accomplish this task, you'll need to resort to the SendMessageAsLong() API function. This function conforms to the following syntax:

Private Declare Function SendMessageAsLong Lib "user32" _
     Alias "SendMessageA" (ByVal hWnd As Long, ByVal wMsg As Long, _
     ByVal wParam As Long, ByVal lParam As Long) As Long


To obtain the number of lines, you pass in the EM_GETLINECOUNT constant in the wMsg parameter. Declare this constant like this:

Const EM_GETLINECOUNT = 186

Finally, to use the function, pass in the handle to the textbox from which you want to retrieve the line count, as well as the wMsg we mentioned earlier. Example code might look like so:

Private Sub Command2_Click()
    Dim lCount As Long
    lCount = SendMessageAsLong(Text1.hWnd, EM_GETLINECOUNT, 0, 0)
    MsgBox lCount
End Sub

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