Re: TextBox border - C# Discussion Boards

TAREQ F ABUZUHRI26-Aug-06 9:23

TAREQ F ABUZUHRI

26-Aug-06 9:23

win form load it will be normal textbox

but when mouse over (the border will be red color)

Palestine

Nader Elshehabi26-Aug-06 22:27

26-Aug-06 22:27

Hello

You'd have to handle MouseEnter and MouseLeave events like this:

private void textBox1_MouseEnter(object sender, EventArgs e)
        {
            Graphics g = textBox1.CreateGraphics();
            g.DrawRectangle(new Pen(Brushes.Red, 3), new Rectangle(0, 0, textBox1.Width - 5, textBox1.Height - 5));
        }

        private void textBox1_MouseLeave(object sender, EventArgs e)
        {
            Graphics g = textBox1.CreateGraphics();
            g.DrawRectangle(new Pen(Brushes.White, 3), new Rectangle(0, 0, textBox1.Width - 5, textBox1.Height - 5));            
        }

Regards

mav.northwind27-Aug-06 6:10

27-Aug-06 6:10

Hi!
That's not a good advice you're giving there.
You're creating resource leaks because you don't dispose of the Graphics object and drawing to the textbox in this way is only visible as long as the textbox isn't redrawn.

Regards,
mav

--
Black holes are the places where god divided by 0...

Nader Elshehabi27-Aug-06 7:38

27-Aug-06 7:38

Hello

mav.northwind wrote:
you don't dispose of the Graphics object

Well, last time I checked my GC wasn't on vacation! Smile | :)

My graphics objects are local variables, they will be disposable once the call to the handler is over.

mav.northwind wrote:
drawing to the textbox in this way is only visible as long as the textbox isn't redrawn.

Unfortunately, no! This is not a webpage where the user may click refresh, and almost all the causes of paint are mouse involved. Once the mouse is out of the box, it doesn't matter!! Even when the user types in the box without moving the mouse out, the box is still there. Besides, this is just a hint. You want to handle the paint event as well, not a problem.

Thanks for the post though.

Regards

mav.northwind27-Aug-06 21:29

27-Aug-06 21:29

ReHi!

Nader Elshehabi wrote:
Well, last time I checked my GC wasn't on vacation! My graphics objects are local variables, they will be disposable once the call to the handler is over

It's not that the GC isn't working correctly, you're not calling Dispose()!
You shoud use:

using (Graphics g = textBox.CreateGraphics())
{
}

Nader Elshehabi wrote:
Unfortunately, no! This is not a webpage where the user may click refresh, and almost all the causes of paint are mouse involved. Once the mouse is out of the box, it doesn't matter!!

Sorry to say that, but this is exactly the cause for many questions in this forum when people ask why they are having problems when they paint directly on top of controls.
The paint event is the only correct place to perform painting.
With your suggestion, just move another window over the textbox (or part of it) and you'll see what I mean.

Regards,
mav

--
Black holes are the places where god divided by 0...

Nader Elshehabi28-Aug-06 1:02

28-Aug-06 1:02

Hello

I don't want to sound like I'm just arguing, but it's nice to have this talk with you.

mav.northwind wrote:
you're not calling Dispose()

Best practice, you should call dispose() I know, but it occurs to me, why to dispose it, if it will be disposed by itself after the event handler is finished??

mav.northwind wrote:
just move another window over the textbox (or part of it) and you'll see what I mean.

How could you do that without moving the mouse out of the textbox first?;P

Again, it's nice to have this talk with you.

Regards

mav.northwind28-Aug-06 3:07

28-Aug-06 3:07

Rehi!

Graphics implements IDisposable and is freeing the native GDI+ graphics handle in its Dispose() method.
When you don't call Dispose() the resource doesn't get freed and your app will crash the computer after a while because it's running out of GDI handles eventually.

Nader Elshehabi wrote:
How could you do that without moving the mouse out of the textbox first?

Alt-Tab? And another Alt-Tab to get back to the original window. The mouse still is inside the TextBox but I'm pretty sure there'll be no red border.

Regards,
mav

--
Black holes are the places where god divided by 0...

Nader Elshehabi28-Aug-06 5:10

28-Aug-06 5:10

Hello

Thank you for your kind advice. I'll make sure to dispose managed objects I create. Also I'd be happy to read an article -specially if you wrote it- about when to dispose and when to leave that to the GC.

About the Alt-Tab!! Nice catch!! Big Grin | :-D

Extra Regards Rose | [Rose]

Nader Elshehabi28-Aug-06 5:19

28-Aug-06 5:19

Hello

If you were following the conversation I as having with mav.. There will be a slight change in the code for the sake of optimization

private bool DrawBox = false;

private void textBox1_MouseEnter(object sender, EventArgs e)
{
    Drawbox = true;
}

private void textBox1_MouseLeave(object sender, EventArgs e)
{
    Drawbox = false;
}

//now draw the Box according to input focus

private void textBox1_Enter(object sender, EventArgs e)
{
    Drawbox = true;
}

private void textBox1_Leave(object sender, EventArgs e)
{
    Drawbox = false;
}

private void textBox1_Paint(object sender, EventArgs e)
{
    Graphics g = textBox1.CreateGraphics();
    if(DrawBox)    
        g.DrawRectangle(new Pen(Brushes.Red, 3), new Rectangle(0, 0, textBox1.Width - 5, textBox1.Height - 5));
    else
        g.DrawRectangle(new Pen(Brushes.White, 3), new Rectangle(0, 0, textBox1.Width - 5, textBox1.Height - 5));
    g.Dispose();
}

i hope that work mav.. Thanks!

Regards

mav.northwind28-Aug-06 8:26

how to add checkbox column in datagrid

28-Aug-06 8:26

Formally, this could work (although you don't have to create a Graphics object - the Paint event has one in its event args - and your rectangles will not be centered), but unfortunately in real life it doesn't.
It's because the TextBox isn't signalling a Paint event to a caller out of the box and thus your rectangle isn't painted.

You could derive from TextBox and set some control styles (UserPaint, mainly), but altogether the effect is not worth the trouble IMO...

Regards,
mav

--
Black holes are the places where god divided by 0...

iramg26-Aug-06 7:35

iramg

26-Aug-06 7:35

i want to add first column of datagrid as checkedbox against every row of datagrid. then from the list i will select some checkboxes according to need.how i will implement this thing plz tell me any simple way.
reply soon.

Re: how to add checkbox column in datagrid

Ed.Poore26-Aug-06 8:58

Re: how to add checkbox column in datagrid

26-Aug-06 8:58

Can you elaborate?

As of how to accomplish this, have you ever tried Google?

iramg26-Aug-06 9:16

iramg

26-Aug-06 9:16

yes i have tried all even i read many articales in codeproject also. they are very complex and webbased. i dont understand them i read one artical

http://www.codeproject.com/aspnet/ChkBoxInGrid.asp

i want to do the same thing but in windows form. i dont understand how to bind checkbox with datagrid.and i want to display checkboxe with every row of datagrid. so plz help me

Re: how to add checkbox column in datagrid

Ed.Poore26-Aug-06 9:37

26-Aug-06 9:37

To add a checkbox column just open the Column designer and add a column of type DataGridViewCheckBox.

If you want to perform the selecting and deselecting etc, why you can just use Control and Shift combinations to achieve the same thing. There should be a property called SelectedRows so you can enumerate them.

As of how to accomplish this, have you ever tried Google?

HTTPS Proxy

WillemM26-Aug-06 7:09

WillemM

26-Aug-06 7:09

I'm working on a HTTP(S) proxy and I got the HTTP part working complete with authentication.
Only HTTPS keeps buggering me, how should I handle this?

Do I need to setup a connection and just relay the data between the client and the server?
Because if I do that, the user is unabe to request another URL afterwards, at least with HTTP 1.1 and internet explorer 6/7 that is.

For HTTP I made the relaying part work by intercepting each request from the client and handle it as if it were a request for the proxy. That works great, but I'm unsure about HTTPS...

Any ideas on how to get this part to work?

WM.

What about weapons of mass-construction?

Invoking an event...

Shy Agam26-Aug-06 6:56

Shy Agam

26-Aug-06 6:56

I have a class library I wrote, which deals with sockets.
I raise events through this library, such as DataArrival (which gives me the problem btw).

This is a snippet from my receiveCallback function:

//Retrieve the buffer.
Buffer bf = (Buffer)result.AsyncState;
//Seperate packs and enqueue them.
bf.QueuePacks();
if (OnDataArrival != null)
{
    //Call EventHandler to process incomming data.
    if (caller != null) caller.Invoke(OnDataArrival, bf);
    else OnDataArrival(bf);
}
//Begin receiving data from the remote computer.
sck.BeginReceive(bf.Data, 0, bf.Data.Length, SocketFlags.None, new AsyncCallback(receiveCallBack), bf);

Buffer is also a class I wrote, and caller is a reference to a form.
This code works most of the time.
I'm currently working on a new project which uses my class.
In this project, I sometimes get an "Parameter is invalid" exception, on this line:

caller.Invoke(OnDataArrival, bf);

It works most of the time, and never happend in my previous projects.

Is it wrong to invoke an event?
What's wrong with my parameters?

Ed.Poore26-Aug-06 9:37

26-Aug-06 9:37

shyagam wrote:
Is it wrong to invoke an event?
What's wrong with my parameters?

Care to provide some more details?

As of how to accomplish this, have you ever tried Google?

Shy Agam26-Aug-06 12:34

Shy Agam

26-Aug-06 12:34

Ed.Poore wrote:
Care to provide some more details?

Well... I don't really know what details I can give you...
Could you please point me in the right direction?

Ed.Poore wrote:
As of how to accomplish this, have you ever tried Google?

Of course! That's how I knew I should use the Invoke method... Smile | :)

Ed.Poore27-Aug-06 8:21

27-Aug-06 8:21

I meant details as to the exception, stack trace etc.

Nader's advice holds strong though.

As of how to accomplish this, have you ever tried Google?

Nader Elshehabi26-Aug-06 21:57