RichTextBox very slow

[kelvin.koogan]

I'm using a RichTextBox in a protocol analyser I'm developing. However
as the amount of data gets large, e.g. 500000 lines, the control
becomes very slow.

For example if I load in a saved file it can take 30 seconds just to
transfer data from a StringBuilder to the RichTextBox, even with
updates turned off with WM_SETREDRAW.

Also I highlight a line when the users clicks on it and this can be
slow, as can be highlighting all instances of a string match.

Is there any way to make actions like adding text to a RichTextBox or
highlighted portions of text any faster?

TIA,
KK

[Herfried K. Wagner [MVP]]

<ke***********@googlemail.comschrieb:

I'm using a RichTextBox in a protocol analyser I'm developing. However
as the amount of data gets large, e.g. 500000 lines, the control
becomes very slow.

For example if I load in a saved file it can take 30 seconds just to
transfer data from a StringBuilder to the RichTextBox, even with
updates turned off with WM_SETREDRAW.

Also I highlight a line when the users clicks on it and this can be
slow, as can be highlighting all instances of a string match.

Is there any way to make actions like adding text to a RichTextBox or
highlighted portions of text any faster?

You can write the RTF code directly instead of selecting text and changing
its properties via the 'Selection*' properties. However, I wonder how a
user should be able to deal with 500,000 lines of text. Maybe you should
consider implementing a paging mechanism or something similar.

--
M S Herfried K. Wagner
M V P <URL:http://dotnet.mvps.org/>
V B <URL:http://dotnet.mvps.org/dotnet/faqs/>

[kelvin.koogan]

On 31 May, 14:29, "Herfried K. Wagner [MVP]" <hirf-spam-me-
[e-mail]:

<[e-mail]:

I'm using a RichTextBox in a protocol analyser I'm developing. However
as the amount of data gets large, e.g. 500000 lines, the control
becomes very slow.

For example if I load in a saved file it can take 30 seconds just to
transfer data from a StringBuilder to the RichTextBox, even with
updates turned off with WM_SETREDRAW.

Also I highlight a line when the users clicks on it and this can be
slow, as can be highlighting all instances of a string match.

Is there any way to make actions like adding text to a RichTextBox or
highlighted portions of text any faster?

You can write the RTF code directly instead of selecting text and changing
its properties via the 'Selection*' properties. *

I'm sorry I don't understand what you mean, could you explain a little
more please?

However, I wonder how a
user should be able to deal with 500,000 lines of text. *Maybe you should
consider implementing a paging mechanism or something similar.

I have considered this but it seems like a lot of work and my
timescales are very tight. Is there any simple way to do this?

TIA,
KK

>
--
*M S * Herfried K. Wagner
M V P *<URL:http://dotnet.mvps.org/>
*V B * <URL:http://dotnet.mvps.org/dotnet/faqs/>