Debug.WriteLine syntax

[ebellounisoft]

I do not have much experience in Debug syntax and can't find in any book or tutorial. I am only going to present the code line for the Debug.WriteLine. The Project runs fine. My problem is to understand the Debug syntax.

1. Debug code line:

Debug.WriteLine("a1) sb1.Length = {0}, sb1.Capacity = {1}", sb1.Length,sb1.Capacity)

2. Result:

a1) sb1.Length = 3, sb1.Capacity = 16

2. What is the meaning (or roll) of:

"a1) sb1.Length = {0}, sb1.Capacity = {1}"

And of:

{0}

and

{1}

[techgnome]

1) you posted in the wrong forum... I'll ask the mods to move it.
2) Did you look at the documentation?

.WriteLine uses a format string, like what String.Format uses. {0} is a place holder. It tells the formatter that the first item in the parameter array is to go into that spot. {1} Means the next item goes in that spot and so on. You can also apply other formatting to the objects depending on what they are, for example, if it is a number, you can indicate if decimals are to be displayed, how many, currency symbol, and so on.

-tg

[ebellounisoft]

The Code for the example is in language Visual Basic.NET from MSN:
https://msdn.microsoft.com/en-us/lib...v=vs.110).aspx

Thank you for your answer.

[Sitten Spynne]

This isn't a special "debug syntax" but instead a more general "string formatting" syntax that many parts of the .NET framework use. I did a sort of mini-tutorial in another thread, but it wasn't focused on explaining the syntax.

Console.WriteLine(), Debug.WriteLine(), and String.Format() use a syntax MS calls "composite formatting" to help you format strings. By way of quick example, these two lines do the same thing:

Dim example As String = "Hello " & someVariable & "!"
Dim example As String = String.Format("Hello {0}!", someVariable")

To make a "format string", you type out a normal string. In places where you want to substitute a variable, you insert an {n} symbol, that is, a curly brace, a number, and a closing curly brace. The numbers should start at 0 and get bigger as the string goes on.

Any method that expects a format string also takes parameters at the end. Parameters are substituted into the string, in order, replacing the {n} symbols you made.

So if you need to put in two symbols:

Console.WriteLine("Hello, {0} {1}!", firstName, lastName)

You can also repeat them:

Console.WriteLine("Hello, {0}{1}{0}{2}", Environment.NewLine, firstName, lastName)

There are some other neat things you can do, but you can read about them in depth at your leisure.

[ebellounisoft]

Now I get it !!!. Thank you.