Re: Check to see if table exists - C# Discussion Boards

Paul Conrad19-Jul-06 20:31

Paul Conrad

19-Jul-06 20:31

You might want to look at this article, A Complete Read Only ComboBox[^]

Or search this site for read only comboboxes. This might help you and you won't have to worry about trapping mouse events.

Hope this helps some,

Paul

Rahul.RK19-Jul-06 20:35

Rahul.RK

19-Jul-06 20:35

Hello my friend,

Just check "DropDownStyle" property of combobox.

Set the property to DropDownList.

Rahul Kulkarni

Paul Conrad19-Jul-06 20:43

Paul Conrad

19-Jul-06 20:43

RahulRKulkarni wrote:
Set the property to DropDownList.

That looks like it works just fine Smile | :)

AnnnS19-Jul-06 20:50

AnnnS

19-Jul-06 20:50

Thanx All for the replies.. let me try it out

Akhil

Big Grin | :-D

VScrollbar within a Panel

Paul Conrad19-Jul-06 20:52

Paul Conrad

19-Jul-06 20:52

akhils wrote:
Thanx All for the replies.. let me try it out

Good luck to you Smile | :)

John Harrison Paul19-Jul-06 18:21

John Harrison Paul

19-Jul-06 18:21

Hi All, I am trying to figure out how to use a VScrollBar within a Panel and a series of textboxs. I have about 25 textbox within a Panel. I want to be able to scroll through the panel if the form is to small to see all the textbox. I tried putting a VScrollBar within the Panel but can't get it to scroll the contents of the panel. I can't use AutoScroll property coz I'm developing for Pocket PC. Dot Net Portal Framework don't have autoscroll property for panel. Can you please tell me how am I gonna change the panel visible area.
Thanks

Check to see if table exists

Saamir19-Jul-06 16:07

Saamir

19-Jul-06 16:07

Hi guys,
In C# how do I check if a table exists on SQL server 2000? If it doesn't exists then I am creating the tables but I would like to check first if the table exists.

Please help.

sasa

Stathread19-Jul-06 18:13

Stathread

19-Jul-06 18:13

an easy way would be to use a try and catch and create the table. SQL wont overwrite the table thus if it exist your program will throw the exception which will be caught. Or you could use the following T-SQL

IF (SELECT count(name) FROM sysobjects WHERE type = 'U' and name = 'yourtable') > 0
BEGIN
Print 'Table Exists!!'
END
else Print 'Table Does not Exist!!'

Saamir20-Jul-06 2:58

Saamir

20-Jul-06 2:58

Thanks for your help. I am using try/catch at the moment but in the future I would like to use your Select statement.

I have a question about the select statement, (name) would that be name of the field in the table, also what is type='U' also don't you need sqlconnection object to run the query?

Please advice.

sasa

Stathread20-Jul-06 16:03

Stathread

20-Jul-06 16:03

Dont change the (name) part but change the part where I put "YourTable" that is where your table name goes. What it will do is count how many tables exist in sysobjects with your table name and if the count is greater than 0 than the table exists. "U" just means its only looking at the user tables and not the sql server tables.

Ron S.

Restoring control's default properties

Stathread20-Jul-06 16:07

Stathread

20-Jul-06 16:07

And, yes you do need a your sql connection ect.

xkx3219-Jul-06 15:58

xkx32

19-Jul-06 15:58

I'm changing a control property at design time (backColor, etc), at some point of the program... I want to restore the control's default properties that I have chosen at design time.

Is that possible?

thankx

Re: Restoring control's default properties

Super Lloyd19-Jul-06 17:15

Super Lloyd

19-Jul-06 17:15

yes!

Getting HTML source displaying [modified]

James Dufty19-Jul-06 15:38

James Dufty

19-Jul-06 15:38

Hi, Im a first time poster long time user of the code project.

I am currently working on a web browser. I have release the beta 1 version (its called: T.I.B. [Beta 1])and people all over the place loved it especially the people that tested it at Cybershack Forums.

I am now making a beta 2 and i have failed many a time to figure out how to get the html source of a webpage to open in a notepad document (.txt) like Microsoft Internet Explorer or for it to open the html source in a richTextBox when the user wants to view the source.

Can somebody help me out here, can you make me a code that will open the html source from a web page in a web browser control that will open in a .txt document or in a richTextBox or even in a pop-up windows form.

P.S. If somebody does manage to help me out here, i will give them credit for their programming in the credits of the my web browser program as a sign of how grateful i am.

Re: Getting HTML source displaying

Stefan Troschuetz19-Jul-06 21:30

Stefan Troschuetz

19-Jul-06 21:30

James Dufty wrote:
or in a richTextBox or even in a pop-up windows form.

Why not combine these two? Create a windows form with a RichTextBox and assign the html source to its Text property.

"Programming today is a race between software engineers striving to build bigger and better idiot-proof programs, and the Universe trying to produce bigger and better idiots. So far, the Universe is winning." - Rick Cook

www.troschuetz.de

Re: Getting HTML source displaying [modified]

Gavin Roberts20-Jul-06 0:23

Gavin Roberts

20-Jul-06 0:23

You can invoke the View Source function in the AxWebBrowser object:

http://support.microsoft.com/?kbid=329014[^]

or you can do this your self by getting the source of the document, and writing it to a text file in your temp folder, then simply launch notepad with the filename as an parameter.

Gav

-- modified at 6:23 Thursday 20th July, 2006

Re: Getting HTML source displaying

James Dufty20-Jul-06 15:35

James Dufty

20-Jul-06 15:35

I still don't get it... perhaps somebody who gets it can make a demo project of this function, it would be good.

passing data to a textbox on a form using a method in a class

haz1319-Jul-06 13:32

19-Jul-06 13:32

I am trying to write data to a textbox I have on a form (Form1) from a method in a class.

In my class I try writing -

public class NumberProcessing
{
public static void UpdateNumArray()
{
Form1.textBox1.text = "hello";
}

but the intellisense does not recognise anything past Form1.

Why can I only access textbox1 when in public partial class Form1 : Form ?

How can I access the textbox property of Form1 from other classes ?

Haz

ROTFLMAO

Ennis Ray Lynch, Jr.19-Jul-06 13:57

Ennis Ray Lynch, Jr.

19-Jul-06 13:57

Sorry, c# is not VB6 you need an object reference to Form1 in order to update it. If you insist on this pattern pass the reference to the form in the NumberProcessing contructor. However, I seriously recommend scrapping it and trying again. From what I see you are about to design something very unmaintainable.

A man said to the universe:
"Sir I exist!"
"However," replied the Universe, "The fact has not created in me A sense of obligation."

-- Stephen Crane

Re: ROTFLMAO

haz1319-Jul-06 14:28

Re: passing data to a textbox on a form using a method in a class

19-Jul-06 14:28

Thanks for your reply. I am very new to C# coming from a C programming background.

I do not fully follow what you mean as I understand constructors to be used when creating an instance of a class (i.e an object) here I am using static type which can not be initialized. If possible could you give me a short example of what you mean?

Basically I want to know how I can get access to the textbox property from a class other than Form1?

Or do I / should I always make reference to to the textbox property from within the Form1 class?

Thanks in advance

Haz

Re: ROTFLMAO

Ennis Ray Lynch, Jr.19-Jul-06 14:40

Ennis Ray Lynch, Jr.

19-Jul-06 14:40

class SomeLogicClass{

    public static void DoSomething(Form form){
        //I can now modify any form at will
    }//end 

    public static void DoSomething(Control control){
        //I can now modify any control, at will
    }//end 

    public static void RegisterForm(Form form){
        //Hrmm maybe listen to an event on the form instead, to do something
    }
}

Also, you can create a singleton class. There are a lot of options. However, the path you are taking I have seen before and it will cause problems in the future. Look for some samples in a c# book as a good guide.

A man said to the universe:
"Sir I exist!"
"However," replied the Universe, "The fact has not created in me A sense of obligation."

-- Stephen Crane

Christian Graus19-Jul-06 19:16

Christian Graus

19-Jul-06 19:16

Trying for a more helpful version of the comment you got...

haz13 wrote:
Form1.textBox1.text = "hello";

Form1 is a class. You need to access an instance of the class to pass a value through. What you're trying to do is a VB6 hack.

The best way to do this is to create a delegate between the two classes. I assume delegates can be static, although I've never seen one. If not, you will need an instance of NumberProcessing inside Form1.

The other way to do it is to create a property on Form1 which sets the text of textbox1, and pass a reference to the Form1 instance that's in use to NumberProcessing. This is less of a hack than what you're doing, but not as nice as the delegate.

I trust the code you're showing is just pseudo code. There is no level on which textbox1 and form1 are acceptable variable names. Also, if your controls are public, change them to protected at least. That's just another poor design that you'll come to regret later.

Christian Graus - Microsoft MVP - C++
Metal Musings - Rex and my new metal blog

Re: passing data to a textbox on a form using a method in a class

AB777119-Jul-06 19:36

AB7771

19-Jul-06 19:36

Yes the use of delegates can do that,
Declare a delegate event handler, implement that event handler
in the Form1 class and invoke that event from the other class where you are trying to set the textbox value and pass the value as a parameter to the delegate.

e.g
public delegate void TextChangeEventHandler(string text);

public delegate void ChangeText;

Then implement this method :
You can just write
this.ChangeText += new TextChangeEventHandler(ChangeText);

then the method
Public void ChangeText(string Text)
{
textbox1.text = Text;
}

and in Your class u can just raise the event
Form1.TextChangeEvent obj = new ...
and obj.Invoke();

Hope that works for you

Regards,
Pramod

Re: passing data to a textbox on a form using a method in a class

haz1322-Jul-06 3:05

Re: passing data to a textbox on a form using a method in a class

22-Jul-06 3:05

Thanks for your more helpful version. I am new to this oop and slowly getting my head around it.

I have gone away and read up on delegates but still fail to understand their use.

I understand what you mean in your second method but am slightly confused about loading a reference into my NumberProcessing class. Surely when creating the instance Form1 which is public(of the form class) Form1 properties and methods should be available to other classes within the same namespace. I don't understand why I can't see them?

OK - accepting you can't see the properties and methods of Form 1 in other classes, how do I load a reference of the Form1 object into my static NumberProcessing class?

Here is my code - the problem is when trying to access Form1.SetFormData(); in the NumberProcessing class.

namespace RouletteV1
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}

private void btn1_Click(object sender, EventArgs e)
{
NumberAttributes.Load(1);
}

public void SetFormData()
{
//here is where I will set the textbox properties

textBox1.Text = "Hello";
}

}
}

--------------

namespace RouletteV1
{
public static class NumberAttributes
{
public void Load(short Number)
{
// load the number data into global properties here

NumberProcessing.UpdateNumArray();
}
}

---------------

namespace RouletteV1
{
public static class NumberProcessing
{

public void UpdateNumArray()
{

// Here I want to call the SetFormData()function in Form1 but it won't recognise it - why???

Form1.SetFormData();

}

}
}

Thanks in advance for your help - Please feel free to comment on what you think to the structure of the program - if you think I have made any other fundamental mistakes

Haz

haz1322-Jul-06 5:27