Drawing line in c# - C# Discussion Boards

Re: Data Mining using C#

David Stone10-Oct-05 10:05

David Stone

10-Oct-05 10:05

Good point. I guess I just assume that everybody should know about RegEx. Smile | :)

Picture a huge catholic cathedral. In it there's many people, including a gregorian monk choir. You know, those who sing beautifully. Then they start singing, in latin, as they always do: "Ad hominem..."
-Jörgen Sigvardsson

Re: Data Mining using C#

XRaheemX10-Oct-05 10:46

XRaheemX

10-Oct-05 10:46

I don't know about you, but RegEx was the most confusing crap in the dev world for me to learn Smile | :)

Re: Data Mining using C#

David Stone10-Oct-05 10:57

David Stone

10-Oct-05 10:57

Really? I found RegEx to be quite easy. I guess it helps to have a good tool like Expresso or The Regulator to play with on some sample data.

Re: Data Mining using C#

XRaheemX10-Oct-05 11:39

XRaheemX

10-Oct-05 11:39

Yeah.. learning the RegEx I guess wasn't that difficult... it's remember all of the syntax that's a pain to me

Re: Data Mining using C#

alvinjv10-Oct-05 23:06

alvinjv

10-Oct-05 23:06

Thanks so much for your help. I have managed to create a project and fixed a few errors. However I keep having a problem with this line:
ParseText(line,ref customClass);
Getting this error:
D:\Documents and Settings\Alvin\My Documents\Visual Studio Projects\File Searcher\Form1.cs(113): An object reference is required for the nonstatic field, method, or property 'File_Searcher.Form1.ParseText(string, ref File_Searcher.MyFile)'

Would really appreciate your help!

Kind Regards

Re: Data Mining using C#

XRaheemX11-Oct-05 3:09

XRaheemX

11-Oct-05 3:09

Wherever you are declaring the object File_Searcher.MyFile you must instantiate it. Example:

File_Searcher.MyFile myFile = new File_Searcher.MyFile();

then on the line use: File_Searcher.Form1.ParseText(string, ref myFile)

Dynamic Image Location in Crystal Report XI

dhol10-Oct-05 2:48

dhol

10-Oct-05 2:48

Hi
I am working with Crystal reports XI. Dynamic Image location is
possible in CR XI... But I couldnt understand teh example given for
dyanmic image location in businessobjects.com...

so please anyone witha small example explain to me how to do it using
c#.

dhol

Drawing line in c#

newtocsharp10-Oct-05 1:20

newtocsharp

10-Oct-05 1:20

Hi all,

I am a beginner in c#. I had used the following code to draw a line as given in the documentation. Line doesn't appear. Am I missing something or is it a painting text problem during refreshing. this code is executed as a part of a handler for a menu item..

<br />
<br />
Line myLine = new Line();<br />
myLine.Stroke = Brushes.Black;<br />
myLine.StrokeThickness = 10;<br />
myLine.StrokeStartLineCap = PenLineCap.Round;<br />
myLine.StrokeEndLineCap = PenLineCap.Round;<br />
myLine.X1 = 10;<br />
myLine.Y1 = 10;<br />
myLine.X2 = 75;<br />
myLine.Y2 = 90;<br />
<br />

Kindly throw light on this..

Thanks,

Re: Drawing line in c#

Christian Graus10-Oct-05 2:09

Christian Graus

10-Oct-05 2:09

I've never, ever seen a Line class in C#. The way to draw a line is to get ahold of the Graphics object for the item being drawn, and then use it's DrawLine method.

Here[^] is an MSDN article on drawing your own menu item, I assume this is what you're trying to do.

Christian Graus - Microsoft MVP - C++

Re: Drawing line in c#

AB777110-Oct-05 22:35

AB7771

10-Oct-05 22:35

Hi,

first you should know on which object do u want to draw the line
such as the form or panel or whatever..
Then create a graphics object for that object and then using that
Graphics object draw the line

e.g

if you want to draw the line on the form
then create the graphics using the CreateGraphics method and
then use the DrawLine() method to draw the line

Hope You get benefited by the above information

Thanks
Pramod

diplaying data in datagrid without child table

Rizwan Bashir10-Oct-05 0:56

Rizwan Bashir

10-Oct-05 0:56

Hello there
I have dataSet containing two relational tables. Say Parent and Child. Now when I assign the Datasource of DataGrid to Parent Table then Child Table automatically attaches and a plus (+) comes with each row containing childs rows from child table. I dont wont to diplay those as I have another grid diplaying the childs.

Can any one help me how to get rid of this.

Re: diplaying data in datagrid without child table

Gavin Jeffrey10-Oct-05 1:33

Gavin Jeffrey

10-Oct-05 1:33

Change your datagrids datasource property to be = parent table and not the dataset

Re: diplaying data in datagrid without child table

Rizwan Bashir10-Oct-05 3:04

Rizwan Bashir

10-Oct-05 3:04

its already the parent table only like this

dg.datasource=dataset.tables["parent"];
even then it shows the child..
any comments ?

Re: diplaying data in datagrid without child table

Gavin Jeffrey10-Oct-05 3:57

Gavin Jeffrey

10-Oct-05 3:57

hmmm...not sure really - what about setting the DataMember
i.e. dg.DataMember = "parent";
or clearing all the relations on the dataset i.e. dataset.Relations.Clear();

please help using references in c#

arusmemon9-Oct-05 22:20

arusmemon

9-Oct-05 22:20

hi,
i want to set a reference of a member variable of a class to a variable passed by reference in one of its methods how to do it

Descriprion:
i am using a dll that has System.Windows.Forms.PictureBox Image; declared as a private member and many of its functions are modifyung this variable, now i want to pass a referece of a picturebox on my form to this dll and i want it to be updated when any of the functions of dll change Image variable.
How to do it

Regards,
Arus

Re: please help using references in c#

Maqsood Ahmed10-Oct-05 0:04

Maqsood Ahmed

10-Oct-05 0:04

Hello,
Use ref keyword. Please see MSDN for more help on ref.
HTH. Cheers

Maqsood Ahmed - MCAD.net
Kolachi Advanced Technologies
http://www.kolachi.net

string conversion

Brendan Vogt9-Oct-05 21:55

Brendan Vogt

9-Oct-05 21:55

I have the following piece of code.

private string strName = null;

if(txtName.Text.Trim() != "")
strName = txtName.Text.Trim();

Isn't there a way to convert and assign the value of txtName to strName like in a convert function? I mean if it is empty assign null to strName, or assign it the value of txtName to strName?

The reason why I ask is because I have about 30 such tests and it takes a lot of space, or number of lines.

Regards

Re: string conversion

Maqsood Ahmed10-Oct-05 0:11

Maqsood Ahmed

10-Oct-05 0:11

You can make your own method which can do this for you... a static utility method. Something similar to following code snippet

public static string GetString(string textBoxString)<br />
{<br />
   if(textBoxString.Trim() != string.Empty)<br />
        return textBoxString.Trim();<br />
   return null;<br />
}

Usage:
string strName = MyClass.GetString(txtName.Text);

HTH. Cheers.

Maqsood Ahmed - MCAD.net
Kolachi Advanced Technologies
http://www.kolachi.net

Re: string conversion

S. Senthil Kumar10-Oct-05 2:05

S. Senthil Kumar

10-Oct-05 2:05

You can "bind" the variable to the textbox. Use something like

class MainForm : Form
{
   string strName;
   TextBox txtName;

   public MainForm()
   {
       InitializeComponent();
       txtName.DataBindings.Add("Text", this, "strName");
   }
}

This way, when the dialog closes with DialogResult.OK, whatever is in txtName.Text will be available in strName. When the dialog loads, it's the other way around, whatever is in strName gets set as txtName.Text.

Regards
Senthil
_____________________________
My Blog | My Articles | WinMacro

Re: string conversion

Brendan Vogt10-Oct-05 2:39

Brendan Vogt

10-Oct-05 2:39

And if it is empty then it will automatically have the value of null? But doing it your way, if the user types in nothing, but presses the spacebar once or twice, then because there is no text, it must assign it null.

Re: string conversion

S. Senthil Kumar10-Oct-05 3:03

S. Senthil Kumar

10-Oct-05 3:03

Well, when you use the string, you can always use it after Trim()ing. The only advantage my code offers is that it saves the trouble of manually setting and getting the value of strName.

Regards
Senthil
_____________________________
My Blog | My Articles | WinMacro

Re: string conversion

Brendan Vogt11-Oct-05 0:44

Brendan Vogt

11-Oct-05 0:44

Hi,

I need to ask a similar question with regards to adding a SQL parameter.

Lets say after conversion the variable strName is null.

If I do the following:

SqlParameter paramName = new SqlParameter("@Name", SqlDbType.NVarChar, 150);
paramName.Value = objPrimeAgency.Name;
objCmd.Parameters.Add(paramName);

objPrimeAgency.Name is the property that returns the value of strName. @Name may contain null. When inserting this parameter to the table, will it contain a null? Is this similar to that DBNull value (can't remember exactly what it is)? Must I then individual check to test if null, other wise add the contents to value?

And then the value of the field. If a variable strName has a length, how do I specify this? Classisc ASP I used Len(strName). And secondly, if strName is null, how do I specify a length for it?

Regards,
Brendan

Re: string conversion

Maqsood Ahmed11-Oct-05 20:55

Maqsood Ahmed

11-Oct-05 20:55

ma se wrote:
@Name may contain null. When inserting this parameter to the table, will it contain a null? Is this similar to that DBNull value

No, null is not similar to DBNull.Value

ma se wrote:
If a variable strName has a length, how do I specify this?

strName.Length property will do.

ma se wrote:
if strName is null, how do I specify a length for it?

You can not get properties of the null objects as it always results in NullReferenceException. It'll be better to put in a null check, and if true assign DBNull.Value instead of the length of the string.

HTH.

Maqsood Ahmed - MCAD.net
Kolachi Advanced Technologies
http://www.kolachi.net

Re: string conversion

Brendan Vogt11-Oct-05 22:04

Brendan Vogt

11-Oct-05 22:04

Thanks for the reply.

I just want to get back to your other method you mentined a couple of days:

Method:

public static string GetString(string textBoxString)<br />
{<br />
     if(textBoxString.Trim() != string.Empty)<br />
          return textBoxString.Trim();<br />
     else<br />
          return null;<br />
}

Usage:
string strName = MyClass.GetString(txtName.Text);

Your return type is a string. If it containe a null, won't it complain because your return type is a null?

If I want to create a similar function like this to return DBNull.Value, can I do the above mentioned if, if enmpty, the I return DBNull.Value? Is this the right way to coding it?

Maqsood Ahmed wrote:
strName.Length property will do.

What if it is an int value?

Maqsood Ahmed wrote:
No, null is not similar to DBNull.Value

When I have a variable that is null and add it to my table, then it seems to add a null value to the field, nulls values look like <null> in SQL Server 2000?

Regards

Re: string conversion

Maqsood Ahmed12-Oct-05 20:13

Maqsood Ahmed

12-Oct-05 20:13

Hello,
First of all, null is not a datatype, it is a keyword which represent null reference. A null reference is reference which does not refer to any object. Also null is the default value for all reference-type objects.

ma se wrote:
If I want to create a similar function like this to return DBNull.Value, can I do the above mentioned if, if enmpty, the I return DBNull.Value? Is this the right way to coding it?

Yes you can do the same for DBNull. You will have change the signature of the method to
public static DBNull GetString(string textBoxString)

ma se wrote:
What if it is an int value?

I could not understand this question.

ma se wrote:
When I have a variable that is null and add it to my table, then it seems to add a null value to the field, nulls values look like in SQL Server 2000?

It is DataColumn's implementation which treats null as DBNull.Value. Therefore it'll save the null values in the DataTable to SQL Server 2000 as DBNull.Value.

Maqsood Ahmed - MCAD.net
Kolachi Advanced Technologies
http://www.kolachi.net

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