Textbox innards

[simonc]

Where are the parameters/properties that control the
internal scroll bars of a text box (something like the
AutoScrollPosition X and Y values of a panel)?

Can you get and set these values with program code or
using an external control on the form?

Grateful for any help, but sincerely hope the answer is
not too complicated.

[Herfried K. Wagner [MVP]]

* "simonc" <an*******@discussions.microsoft.com> scripsit:

Where are the parameters/properties that control the
internal scroll bars of a text box (something like the
AutoScrollPosition X and Y values of a panel)?

Can you get and set these values with program code or
using an external control on the form?

You can use pinvoke on 'SendMessage' + 'EM_SETSCROLLPOS'. Notice that
this will only work with the _RichTextBox_, not the simple textbox.

--
Herfried K. Wagner
MVP · VB Classic, VB.NET
<http://www.mvps.org/dotnet>

<http://www.plig.net/nnq/nquote.html>

[simonc]

Thanks for this information. Unfortunately I have never
used any of these commands and am not really sure how to.
Please could you give an example.

Many thanks

Simon C

-----Original Message-----
* "simonc" <an*******@discussions.microsoft.com> scripsit:

Where are the parameters/properties that control the
internal scroll bars of a text box (something like the
AutoScrollPosition X and Y values of a panel)?

Can you get and set these values with program code or
using an external control on the form?
You can use pinvoke on 'SendMessage'

+ 'EM_SETSCROLLPOS'. Notice thatthis will only work with the _RichTextBox_, not the simple textbox.
--
Herfried K. Wagner
MVP · VB Classic, VB.NET
<http://www.mvps.org/dotnet>

<http://www.plig.net/nnq/nquote.html>
.

[Herfried K. Wagner [MVP]]

* "simonc" <an*******@discussions.microsoft.com> scripsit:

Thanks for this information. Unfortunately I have never
used any of these commands and am not really sure how to.
Please could you give an example.

Untested:

Use a RichTextBox control instead of the simple textbox. Untested (have a
look at the MSDN libarary for usage of 'EM_GETSCROLLPOS' and
'EM_SETSCROLLPOS'):

\\\
Private Declare Auto Function SendMessage Lib "user32.dll" ( _
ByVal hwnd As IntPtr, _
ByVal wMsg As Int32, _
ByVal wParam As Int32, _
ByRef lParam As POINTAPI _
) As Int32

Private Const WM_USER As Int32 = &H400
Private Const EM_GETSCROLLPOS As Int32 = (WM_USER + 221)
Private Const EM_SETSCROLLPOS As Int32 = (WM_USER + 222)

Private Structure POINTAPI
Public x As Int32
Public y As Int32
End Structure
///

Usage:

\\\
Dim pt As POINTAPI
pt.x = ...
pt.y = ...
SendMessage(Me.RichTextBox1.Handle, EM_SETSCROLLPOS, 0, pt)
///

--
Herfried K. Wagner
MVP · VB Classic, VB.NET
<http://www.mvps.org/dotnet>

<http://www.plig.net/nnq/nquote.html>

[simonc]

Thank you very much. This code works fine.

The one thing I can't work out is how to send the message
whenever either scrollbar is moved. Because the scroll
bars are internal to the rich text box there doesn't seem
to be an accesible Scroll event that can trigger the
message. Is there a way of doing this?

Many thanks

-----Original Message-----
* "simonc" <an*******@discussions.microsoft.com> scripsit:

Thanks for this information. Unfortunately I have never
used any of these commands and am not really sure how to. Please could you give an example.
Untested:

Use a RichTextBox control instead of the simple textbox.

Untested (have alook at the MSDN libarary for usage of 'EM_GETSCROLLPOS' and'EM_SETSCROLLPOS'):

\\\
Private Declare Auto Function SendMessage Lib "user32.dll" ( _ ByVal hwnd As IntPtr, _
ByVal wMsg As Int32, _
ByVal wParam As Int32, _
ByRef lParam As POINTAPI _
) As Int32

Private Const WM_USER As Int32 = &H400
Private Const EM_GETSCROLLPOS As Int32 = (WM_USER + 221)
Private Const EM_SETSCROLLPOS As Int32 = (WM_USER + 222)

Private Structure POINTAPI
Public x As Int32
Public y As Int32
End Structure
///

Usage:

\\\
Dim pt As POINTAPI
pt.x = ...
pt.y = ...
SendMessage(Me.RichTextBox1.Handle, EM_SETSCROLLPOS, 0, pt)///

--
Herfried K. Wagner
MVP · VB Classic, VB.NET
<http://www.mvps.org/dotnet>

<http://www.plig.net/nnq/nquote.html>
.