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wheelerbarry wrote: This class is a decent basic overview, but due to the massive variations between types of car, you could consider making it abstract and defining specific types of car.
Considering the OP isnt even proficient in defining objects yet, I tried to stear clear of the obvious abstractions.
Of course, the base class should be called Vehicle allowing definition of a Boat (no wheels, still with engine), Bycycle (2 wheels, no engine/gearbox) etc etc etc.
My answer was simply to give a basic layout of a class, which i think is what the OP asked for!
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Hi,
I am working on a Windows based project using C#.
Using VS 1.1 version.
I am using a datagrid.I have a problem, that if the user
modifies the data in the grid, how will we come to know
that there is a change in value in the grid.
I am not using DataSet...i am using a DataGrid
Plz help me to solve the prob,since i am new to C#
Thanks in advance
Regards,
Vaishali
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how you fill the rows in the grid , what is your data source ??
Tamimi - Code
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hi,
i made a access database and view it on a datagrid, i did this by using the datasource,ea in the toolbar. i can add rows to my database, but i cant find the way to delete one. i can delete one in the datagrid but it is not gone in my database. i tried this code:
try
{
tabel1TableAdapter.Update(db1DataSet.tabel1);
db1DataSet.AcceptChanges();
// refresh after the delete
this.tabel1TableAdapter.Fill(this.db1DataSet.tabel1);
Application.DoEvents();
}
catch (System.Exception ex)
{
db1DataSet.RejectChanges();
lbl_error.Text= ex.Message;
}
but i get an error because there is nog valid delete command,
so i looked that op, now i dont know how to create a deletecommand using the tableadapter that was build by the wizard in the beginning by using the toolbar.
can anybody help, or is there another way to delete items without having an error 
thx
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See here[^] maybe it is some helpful to you
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Hello Everyone,
I've got a little problem that I can't seem to find a straight answer to so I'm throwing it out there for you guys to take a stab at it.
I have a UserControl being developed that has two panel controls.
I have already set the designer attribute to allow child controls at design time
<br />
[DesignerCategoryAttribute("Component")]<br />
[Designer("System.Windows.Forms.Design.ParentControlDesigner, System.Design", typeof(IDesigner))]<br />
[ToolboxBitmap(typeof(XPanel),"Image1.bmp")]<br />
public partial class XPanel : UserControl<br />
now i can drag a control on it as is no problem.
what i need to do is when a control is added send it to one of the internal panel's controls collection.
i've tried using the ControlAdded and ControlRemoved events to accomplish this
<br />
private void XPanel_ControlAdded(object sender, ControlEventArgs e)<br />
{<br />
this.DockingPanel.Controls.Add(e.Control);<br />
}<br />
<br />
private void XPanel_ControlRemoved(object sender, ControlEventArgs e)<br />
{<br />
this.DockingPanel.Controls.Remove(e.Control);<br />
}<br />
when i drag a control on to it now i get a pop up in visual studio that says
'child' is not a child control of this parent
if someone could tell me what i'm doing wrong or what i'm missing it would be greatly appreciated.
Ryan Strope
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Hello,
I think the problem is the ControlRemoved EventHandler.
If you add a Control the code in the ControlAdded EventHandler has the effect, that also the code in ControlRemoved is going to be worked threw.
Maybe the solution is to set a boolean flag in the ControlAdded code.
private bool comesfromdesigner=true;
Try that:
private void XPanel_ControlAdded(object sender, ControlEventArgs e)
{
comesfromdesigner = false;
this.XPanel.Controls.Remove(e.Control);
this.DockingPanel.Controls.Add(e.Control);
comesfromdesigner = true;
}
private void XPanel_ControlRemoved(object sender, ControlEventArgs e)
{
if(comesfromdesigner)
this.DockingPanel.Controls.Remove(e.Control);
}
But I'm not sure if you need the ControlRemove code at all!
All the best,
Martin
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Thanks for the effort but no dice there,
tried that and it still didn't work.
Sorry for the short response on the way into the office
Ryan Strope
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How can i delete a file created by FileStream
sAqIb
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You can delete all files in the same way:
System.IO.File.Delete("path");
When you ask specifically about files created by a FileStream, then I guess you have a problem with the file being locked.
This can happen if an exception occurs while you are working with the filestream, or if you haven't released the file from the stream again before deleting it.
You should always use Structured Exception Handling when using I/O operations in code:
using System;
using System.IO;
namespace Testing
{
public class Test
{
public static void Main()
{
FileStream fs = null;
try
{
fs = new FileStream(@"c:\test.txt", FileMode.Create);
byte[] content = new System.Text.UTF8Encoding(true).GetBytes("Hi there!");
fs.Write(content, 0, 9);
}
catch (IOException ioe)
{
Console.WriteLine("Something happened");
if(fs != null)
fs.Close();
}
}
}
}
In this case the file will always be closed, and you should be able to delete it.
Kind regards - Jakob 
*********************************************
Three kinds of people in the world:
- Those who can count..
- Those who can't!
10 kinds of people in the world:
- Those who understand binary
- Those who don't
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Actually, this code won't work. Catch only runs when an exception occurs, I believe you meant to put the fs.Close code in a finally block ?
Christian Graus - Microsoft MVP - C++
Metal Musings - Rex and my new metal blog
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Hehe... that's what you get for replying to a forum post before the first cup'o'mocca in the morning 
You're right of course 
Corrected code reads:
using System;
using System.IO;
namespace Testing{
public class Test
{
public static void Main()
{
FileStream fs = null;
try
{
fs = new FileStream(@"c:\test.txt", FileMode.Create);
byte[] content = new System.Text.UTF8Encoding(true).GetBytes("Hi there!");
fs.Write(content, 0, 9);
}
catch (IOException ioe)
{
Console.WriteLine("Something happened");
}
finally
{
if(fs != null)
fs.Close();
}
}
}
}
Thx for the correction Christian!
Kind regards - Jakob
*********************************************
Three kinds of people in the world:
- Those who can count..
- Those who can't!
10 kinds of people in the world:
- Those who understand binary
- Those who don't
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thanks buddy.
System.IO.File.Delete("path"); worked for me.
sAqIb
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Great!
Kind regards - Jakob
*********************************************
Three kinds of people in the world:
- Those who can count..
- Those who can't!
10 kinds of people in the world:
- Those who understand binary
- Those who don't
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how can i create mobile projects in C#?
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Hi,
I want to transfer the file from client to server.
Just using IPadress only, here i dont use asp and web services.
Any one kindly guide me.
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Hi All
We are using te code below for XML parsing, Its a bit slow, anybody knows fater XML parsing in c#?
As I am using for PocketPC, its taking for ever to parse.
please help.
public static ArrayList ParseURL(string strUrl)
{
ArrayList searchItems = new ArrayList();
mbitSearchItem currentSearchItem = new mbitSearchItem();
string lastElementName = "";
try
{
XmlTextReader reader = new XmlTextReader(strUrl);
while (reader.Read())
{
switch (reader.NodeType)
{
case XmlNodeType.Text:
switch (lastElementName)
{
case "id":
currentSearchItem.id = Convert.ToInt32(reader.Value);
break;
case "fsz":
currentSearchItem.size = Convert.ToInt32(reader.Value);
break;
case "fnm":
currentSearchItem.name = reader.Value;
break;
case "typ":
currentSearchItem.type = Convert.ToInt32(reader.Value);
break;
case "seed":
currentSearchItem.seeders = Convert.ToInt32(reader.Value);
break;
}
break;
case XmlNodeType.Element:
lastElementName = reader.Name;
//Console.WriteLine(lastElementName);
Hashtable attributes = new Hashtable();
string strURI = reader.NamespaceURI;
string strName = reader.Name;
if (reader.HasAttributes)
{
for (int i = 0; i < reader.AttributeCount; i++)
{
reader.MoveToAttribute(i);
attributes.Add(reader.Name, reader.Value);
}
}
StartElement(strURI, strName, strName, attributes);
break;
case XmlNodeType.EndElement:
if (reader.Name.Equals("item"))
{
searchItems.Add(currentSearchItem);
currentSearchItem = new mbitSearchItem();
}
break;
default:
break;
}
}
}
catch (Exception e)
{
Console.WriteLine("error occured: " + e.Message);
}
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You may want to try to changing the xml data type of your integer values to be xsd:integer (or xsd:decimal) instead of converting the text types yourself. I've found the Convert functions to be fairly slow. In .NET 2 you can try
XmlReader.ReadContentAsInt Method. This, or something else to get rid of the ToInt32 calls, may be faster.
-- Bob
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Hi Bob
I am implementing XmlReader.ReadContentAsInt Method.Now my application builds faster.
Thanks a lot
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Perhaps I have a problem with public/private?
I have a Form generated in C#, the second Form called "MainForm" is included in the Project and visible in the projectexplorer, like a normaly generated Form.
But on de Code of Form1 or so, I can't access to "MainForm"? Its declared as public. I don't understand why MainForm.show etc doesnt work?
Any suggestions?
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Because MainForm is a class name. You can't show a class, only an instance of a class.
private MainForm form;
...
form.Show();
Christian Graus - Microsoft MVP - C++
Metal Musings - Rex and my new metal blog
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That means i have to instanciate (or how its called in english) the class?
1. Has the class MainForm to be public or is that not necesarry?
2. How can i access to MainForm? Do I have to do this like :
Mainformfoo Mainform = new Mainformfoo();
I've read http://www.csharp-station.com/Tutorials/Lesson07.aspx[^] but I didn't see the solution... perhaps I'll change to VB 
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The class needs to be visible to where you're calling it from. The instance does not have to be public, no.
Yes, that's how you create an instance of the MainformFoo class. Remember, this is one instance, if you create OTHER instances, interacting with those will not effect the instance you created before. So if you want to change some property on your form, you can't just do the above to get an instance and call methods, that will not change any other instance in your code.
Christian Graus - Microsoft MVP - C++
Metal Musings - Rex and my new metal blog
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