C#NET2008 Using WITH

[lenniekuah]

Hullo Good Guys,
I need your help.

I am very puzzled about using WITH with C#NET2008.

The coding below when used in VB.NET
I will be using WITH :

Wth me.ListBoxCust
    .ColumnWidth = this.ListBoxCust.Width;
    .DisplayMember = "Companyname";
    .ValueMember  ="CustomerID";
    .DataSource = DS.Tables["Cust"];
End with
 

------------------------------------------------
When coding with C#NET2008 how do I use WITH
on the same coding as above


this.ListBoxCust.ColumnWidth = this.ListBoxCust.Width;
this.ListBoxCust.DisplayMember = "Companyname";
this.ListBoxCust.ValueMember ="CustomerID";
this.ListBoxCust.DataSource = DS.Tables["Cust"];

[hype261]

I don't believe there is an equivalent of the With in the C# language. Other than that you don't have to use this unless you have a naming conflict. The only time you have to use this is in the situation below assuming your class has a member variable x and some method called foo.

public foo(int x)
{
 
this.x = x;
 
}
 

[lenniekuah]

Hi Hype 1261,
thank you for sharing your thought with me.
The reason of me wanting to use WITH in C#NET2008 is to reduce the coding. I did not realised that it does not works in C#NET2008

[Aimee Bailey]

In VB.Net the With statement is a short-cut that I, and many others feel is an ugly way of going about things, in c# the statement was not included because the following is much the same, and reads more logically:

TimeSpan a = ALongVariableName;
 
MessageBox.Show(a.Days.ToString());
MessageBox.Show(a.Hours.ToString());
MessageBox.Show(a.Minutes.ToString());
 

Hope this helps.

Aimee.

[Christian Binder]

There's no equivalent in c#, but you are able to initialize on creation of the object, e.g.

this.ListBoxCust = new ListBox() {
  ColumnWidth = this.ListBoxCust.Width, //I don't know if this line works ...
  DisplayMember = "Companyname",
  ValueMember ="CustomerID",
  DataSource = DS.Tables["Cust"]
};
 

If you'd like to use With for structural purposes, you can use regions or curly brackets e.g.

{
  this.ListBoxCust.ColumnWidth = this.ListBoxCust.Width;
  this.ListBoxCust.DisplayMember = "Companyname";
  this.ListBoxCust.ValueMember ="CustomerID";
  this.ListBoxCust.DataSource = DS.Tables["Cust"]; 
}
 
//or
#region ListBoxCust-Initialization
  this.ListBoxCust.ColumnWidth = this.ListBoxCust.Width;
  this.ListBoxCust.DisplayMember = "Companyname";
  this.ListBoxCust.ValueMember ="CustomerID";
  this.ListBoxCust.DataSource = DS.Tables["Cust"]; 
#endregion ListBoxCust-Initialization
 

[GaryTexmo]

In VB.Net the With statement is a short-cut that I, and many others feel is an ugly way of going about things, in c# the statement was not included because the following is much the same, and reads more logically:

TimeSpan a = ALongVariableName;
 
MessageBox.Show(a.Days.ToString());
MessageBox.Show(a.Hours.ToString());
MessageBox.Show(a.Minutes.ToString());

Hope this helps.

Aimee.

Just a quick note on this... when you do stuff like this I think it's best to do it in a using statement.

using (TimeSpan a = ALongVariableName)
{
  MessageBox.Show(a.Days.ToString());
  ...
}

The reason for this is that anything in that using statement gets disposed of at the end of the scope. I did some tests a while back and it looks like objects don't necessarily get destroyed right as they go out of scope, they hang around until the GC feels like cleaning things up. Doing this, your memory allocation for a will be gone at the end of the using statement.

Just keeps things tidy :)

[Curtis Rutland]

I typically only use the using statements for objects that implement IDisposable.

You are correct about garbage collection (it happens when the environment decides it's necessary), but it's not such a bad thing.

On the other hand, there are several object types that must be disposed of, such as Streams and DataConnections. The great thing about the using statement is that the Dispose method of any IDisposable is called upon exiting the block.

You can manually handle this if you have to use an object across multiple scopes, but it's nice to be able to do:

using(StreamWriter sw = new StreamWriter(path))
  sw.Write(output);

And not have to worry about flushing and closing my stream.

We've gone far afield though. As others have pointed out, there is no equivalent of with in C#. The closest you can get to that is initializing properties upon creation, as Christian mentioned.

[Aimee Bailey]

Only fear id have with using using's (get it ;)) so often, would be that the following:

using (TimeSpan a = ALongVariableName)
{
   MessageBox.Show(a.Days.ToString());
   ...
}
 

might also dispose the variable ALongVariableName, I think when it come's to C#, sometimes we just have to trust that the GC knows what its doing, plus on the bright side, its better than the one in mono hehe.

Aimee.

[GaryTexmo]

My first thought when I read that was, "There's no way Microsoft would be that dumb!" and yet, here we are.

            Form theForm = new Form();
            theForm.Disposed += new EventHandler(theForm_Disposed);
            theForm.Text = "This is a form!";
 
            Console.WriteLine(theForm.Text);
 
            using (Form a = theForm)
            {
                Console.WriteLine(a.Size);
            }
 
            theForm.ShowDialog();
            Console.WriteLine(theForm.Text);

The ShowDialog line throws a disposed exception... you are indeed correct, Aimee. In light of this, I don't think it's appropriate to use what I suggested as an alternative to VB's "with" after all.

Good catch!

[Curtis Rutland]

It's not really dumb, it's an intended thing. They mention it on the MSDN page for "using statement." They also mention that it's not a recommended usage, because of that exact issue.