what does {} do in .net? [RESOLVED]

I am looking at the indexof() and one of the examples shows this:

Console.WriteLine("All occurrences of 'he' from position {0} to {1}.", start, [end] - 1)
Console.WriteLine("{1}{0}{2}{0}{3}{0}", Environment.NewLine, br1, br2, str)

what will the output be?



here's the full example:

Code:

---

Dim br1 As String = "0----+----1----+----2----+----3----+----4----+----5----+----6----+-"
      Dim br2 As String = "0123456789012345678901234567890123456789012345678901234567890123456"
      Dim str As String = "Now is the time for all good men to come to the aid of their party."
      Dim start As Integer
      Dim at As Integer
      Dim [end] As Integer
      Dim count As Integer
     
      [end] = str.Length
      start = [end] / 2
      Console.WriteLine()
      Console.WriteLine("All occurrences of 'he' from position {0} to {1}.", start, [end] - 1)
      Console.WriteLine("{1}{0}{2}{0}{3}{0}", Environment.NewLine, br1, br2, str)
      Console.Write("The string 'he' occurs at position(s): ")
     
      count = 0
      at = 0
      While start <= [end] AndAlso at > - 1
        ' start+count must be a position within -str-.
        count = [end] - start
        at = str.IndexOf("he", start, count)
        If at = - 1 Then
            Exit While
        End If
        Console.Write("{0} ", at)
        start = at + 1
      End While
      Console.WriteLine()

---

It's just a variable in const string . Consider these examples (test them to understand what actually they do ) :

VB Code:

Private Sub ExampleOne()
        Dim strng As String = "World"
        Console.Write("Hello {0}", strng)
        Console.Read()
    End Sub
 
{0} , this means : include the variable indexed 0 in the paramters list passed to Write method . 
 
    Private Sub ExampleTwo()
        Dim sring1 As String = "VB"
        Dim string2 As String = ".NET"
        Console.Write(" {0}{1} Forums", sring1, string2)
        Console.Read()
    End Sub

{0}{1} , this means : include the variables number 0 and 1 in the paramters list passed to Write method .




They are equal to this :

VB Code:

Private Sub ExampleOne()
        Dim strng As String = "Hello World"
        Console.Write(strng)
        Console.Read()
    End Sub
 
 
    Private Sub ExampleTwo()
        Console.Write("VB.NET Forums")
        Console.Read()
    End Sub

thanks Pirate. I assumed it had something to do like that. I saw another example but it was a LOT harder to understand.

Code:

---

Console.WriteLine("Bill total:" + ControlChars.Tab + "{0,8:c}", billTotal)

---

I dont understand what the 0, 8:c represents.

another thing, are there any major differences from console.write and .writeline? They apear to do the same job.

Quote:

---

Originally posted by thephantom
thanks Pirate. I assumed it had something to do like that. I saw another example but it was a LOT harder to understand.

Code:

---

Console.WriteLine("Bill total:" + ControlChars.Tab + "{0,8:c}", billTotal)

---

I dont understand what the 0, 8:c represents.

another thing, are there any major differences from console.write and .writeline? They apear to do the same job.

---

WriteLine : It writes to the console and stop in the next new line .

Write : Writes to the console and stop where the last character was typed . Consider this example (call one of them at a time )

VB Code:

Private Sub WriteLineTest()
        Console.WriteLine("This uses WriteLine Method")
        Console.Read()
 
    End Sub
 
    Private Sub WriteTest()
        Console.Write("This uses Write Method")
        Console.Read()
    End Sub

oh ok, that makes sense. Thanks alot!!

what about the 8:c part?

Quote:

---

Originally posted by thephantom
what about the 8:c part?

---

I don't know . What's the output anyway ?

well, don't really know. I had a bit of trouble figuring out how to place the code in my "test" project.

Code:

---

Public Class TipCalculator
  Private Const tipRate As Double = 0.18
 
  'Entry point which delegates to C-style main Private Function
  Public Overloads Shared Sub Main()
      System.Environment.ExitCode = Main(System.Environment.GetCommandLineArgs())
  End Sub
 
  Overloads Public Shared Function Main(args() As String) As Integer
      Dim billTotal As Double
      If args.Length < 2 Then
        Console.WriteLine("usage: TIPCALC total")
        Return 1
      Else
        Try
            billTotal = Double.Parse(args(1))
        Catch
            Console.WriteLine("usage: TIPCALC total")
            Return 1
        End Try
        Dim tip As Double = billTotal * tipRate
        Console.WriteLine()
        Console.WriteLine("Bill total:" + ControlChars.Tab + "{0,8:c}", billTotal)
        Console.WriteLine("Tip total/rate:" + ControlChars.Tab + "{0,8:c} ({1:p1})", tip, tipRate)
        Console.WriteLine("".PadRight(24, "-"c))
        Console.WriteLine("Grand total:" + ControlChars.Tab + "{0,8:c}", billTotal + tip)
        Return 0
      End If
  End Function 'Main
End Class 'TipCalculator

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that's what is in the msdn. maybe you can make heads and tails of it?

where did you see {0,8:c} used???

I've always seen it like this (C# Code)

VB Code:

double billTotal = 15.56;
 
Console.WriteLine("Bill Total: {0:c}", billTotal);

The {0:c} takes the variable billTotal and formats it as currency (c)

This is all string formatting. When you have {0,8:c}, it's saying this is the 0 index (parameter specifier). The ,8 is the alignment component, and the c (as already stated) is the format string component.

The alignment component allows one to specify the preferred width of the field.

Search MSDN for "Composite Formatting"

Thanks mike! the msdn is great WHEN you know what to look up!! :):)