Ask a Language Designer: boolean: C# vs. Xml

Metro Sauper

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Oct 24, 2003, 12:12:21 PM10/24/03

to

Why is the default text representation for booleans in C# 'True' and 'False'
whereas in xml it is 'true' and 'false'?

It seems like it would make sense to have them both the same.

Metro T. Sauper, Jr.
President
Sauper Associates, Inc.

Greg Ewing [MVP]

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Oct 24, 2003, 12:49:54 PM10/24/03

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Metro, I'm not sure what you mean by the default text representation of a
boolean. In C# code booleans appear as true and false. WRT to making them
the same as XML, there is no connection between XML and C# other than C# can
read, write and process XML. One could ask the same thing as to why in
VB.Net they are True and False vs true and false, or C++, or probably many
different languages. I'm curious why you would think that C# syntax or
defaults should be driven by one standard (xml) over any other.

What are you doing that brought this up?

--
Greg Ewing [MVP]
http://www.citidc.com/

"Metro Sauper" <msa...@sauper.com> wrote in message
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Jon Skeet [C# MVP]

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Oct 24, 2003, 1:55:27 PM10/24/03

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Greg Ewing [MVP] <gewing@_NO_SPAM_citidc.com> wrote:
> Metro, I'm not sure what you mean by the default text representation of a
> boolean.

Try this:

using System;

public class Test
{
static void Main()
{
Console.WriteLine (true.ToString());
Console.WriteLine (false.ToString());
}
}

That prints:

True
False

I'm pretty sure that's what the OP was talking about.

It's not C# that does this, of course, but .NET itself.

--
Jon Skeet - <sk...@pobox.com>
http://www.pobox.com/~skeet
If replying to the group, please do not mail me too

Greg Ewing [MVP]

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Oct 24, 2003, 2:42:09 PM10/24/03

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Ah, I see. Metro, is that what you are talking about?

--
Greg Ewing [MVP]
http://www.citidc.com/

"Jon Skeet [C# MVP]" <sk...@pobox.com> wrote in message
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Michael A. Covington

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Oct 24, 2003, 9:15:00 PM10/24/03

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In .NET, they are (I think) Boolean.True and Boolean.False. In C#, they are
true and false. .NET isn't C#.

Jeffrey Tan[MSFT]

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Oct 25, 2003, 12:25:31 AM10/25/03

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Hi,

I think the true, false in C# are the type value of C#, and it is the
mapping of .Net Framework type value. While in .Net, this type value is
True and False.
This is similiar as the int vs Int32, string vs String type mapping
relationship.

Hope this help,

Jeffrey Tan
Microsoft Online Partner Support
Get Secure! - www.microsoft.com/security
This posting is provided "as is" with no warranties and confers no rights.

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| From: Jon Skeet [C# MVP] <sk...@pobox.com>
| Subject: Re: Ask a Language Designer: boolean: C# vs. Xml
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Metro Sauper

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Oct 25, 2003, 1:19:47 AM10/25/03

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The specific issue that brought this to mind is as follows:

We are using xml to store some default configuration for reports. An xml
entry might appear as follows:

Now normally with xml, we use "XmlConvert.ToBoolean(string)" to convert
values from xml to the specific datatype, in this case boolean.

However, because the datatype is defined in the entry and not predefined, I
wanted to use the Convert.ChangeType() method to evaluate the entry.
Somthing like:

object parameterValue = Convert.ChanageType(node.Attributes["Value"].Value,
System.GetType(node.Attributes[Type].Value));

However, this did not work because we configured the value as "true" rather
than "True". So now our configuration xml has "true/false" everywhere there
are boolean values EXCEPT for the parameter values where the value is
"True/False" since we use the XmlConvert for all values other than the ones
where we would like to use Convert.ChangeType().

Now, I know how to solve the problem. There are lots of ways to solve it.
That is not the question. I posed the question after reading the other "Ask
a Language Designer" questions and responded to the offer to post a question
here.

The question is "Why are the default text representations for boolean
different in .Net and XML?"

Thank you for you consideration of this question.

Metro T. Sauper, Jr.
President
Sauper Associates, Inc.

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Jeffrey Tan[MSFT]

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Oct 25, 2003, 4:32:28 AM10/25/03

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Hi Metro,

Thanks for your feedback.
I think our discussion already shows that in C# the bool type's value are
true and false, while the bool type is mapping to the .Net Framework
Boolean type and its value are True and False.

Does this answer your question?

Best regards,

Jeffrey Tan
Microsoft Online Partner Support
Get Secure! - www.microsoft.com/security
This posting is provided "as is" with no warranties and confers no rights.

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Metro Sauper

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Oct 25, 2003, 9:02:26 PM10/25/03

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Hi Jeffery,

Well actually no. It doesn't answer my question.

I do understand what you are saying. We realized this the moment we
encountered the problem and changed our program accordingly.

Perhaps I expected too much when posting my original question. I was
looking for someone "in the know" to explain to me why the values were
different in the first place. What the "aha!" answer was that would make me
understand why the values need to be different in the first place -- that
there was more reason than the .Net implementors flipped a coin and
"capital" 'F' and 'T' won.

There is really no reason to continue this thread. I understand the
technical aspects of the issue.

Best regards,

Metro.

--------------------------------

Metro T. Sauper, Jr.
President
Sauper Associates, Inc.

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