Setting StringBuilder.Length not behaving per documentation

[donnie.hale]

Perhaps this has been discussed elsewhere - if so, I couldn't find it.

The StringBuilder.Length property is explicitly documented as padding
the length with spaces if .Length is set to a value greater than the
current length. I'm hoping to get this behavior. However, when I set
..Length to something greater than the current length, the padding is
done with null characters ('\0'), not spaces. Is this the actual
intended behavior (and the docs are wrong) or a bug (and the docs are
right)?

Any help in this would be appreciated. Thanks,

Donnie

[Marc Gravell]

It looks like the docs changed:
http://msdn.microsoft.com/library/de...engthtopic.asp
vs
http://msdn2.microsoft.com/en-us/lib...er.length.aspx

I guess you would have to just find the number of spaces you are
"missing", and append via the string ctor that accepts a char and a
count (int).

Marc

[donnie.hale]

Marc,

The workaround is, prior to calling StringBuilder.ToString(), to call
StringBuilder.Replace('\0', ' '). But the docs and the actual behavior
need to match. So I'm trying to get some "official" clarification as to
what's right and what I should expect.

Donnie
Marc Gravell wrote:

It looks like the docs changed:
http://msdn.microsoft.com/library/de...engthtopic.asp
vs
http://msdn2.microsoft.com/en-us/lib...er.length.aspx

I guess you would have to just find the number of spaces you are
"missing", and append via the string ctor that accepts a char and a
count (int).

Marc

[Willy Denoyette [MVP]]

http://msdn2.microsoft.com/en-us/lib....aspxdescribes the correct behavior for all versions of the framework, theprevious documentation was simply wrong.Willy.<do*********@gmail.comwrote in messagenews:11**********************@i3g2000cwc.go oglegroups.com...| Marc,|| The workaround is, prior to calling StringBuilder.ToString(), to call| StringBuilder.Replace('\0', ' '). But the docs and the actual behavior| need to match. So I'm trying to get some "official" clarification as to| what's right and what I should expect.|| Donnie||| Marc Gravell wrote:| It looks like the docs changed:| >http://msdn.microsoft.com/library/default.asp?url=/library/en-us/cpref/html/frlrfsystemtextstringbuilderclasslengthtopic.asp| vs| >http://msdn2.microsoft.com/en-us/library/system.text.stringbuilder.length.aspx| >| I guess you would have to just find the number of spaces you are| "missing", and append via the string ctor that accepts a char and a| count (int).| >| Marc|

[Marc Gravell]

Well, that assumes that your string doesn't include any null characters
at any other places... plus has the overhead of inspecting each
character in the builder so far, which .Append(new string(' ',
padLength)) doesn't; .ToString().PadRight(overallLength) is also an
option, but duplicates the (potentially large) string (efficiency claim
here assumes the padding is shorter than the content).

Re the docs matching, the fact that the docs have changed in line with
your observation suggests strongly that the original documentation was
wrong (or possibly that they were right, but fixing the bug would have
been a potentially breaking change, so it was preferable to change the
documentation). Either way, I believe that MSDN2 tells you what you
should expect to see, which agrees with what you are seeing. But MS
would be able to give a more definitive answer.

Marc

[donnie.hale]

Willy,

Thanks for pointing me at better docs. I was looking at

http://msdn.microsoft.com/library/de...engthtopic.asp

(though I started my search for the Length property at msdn2. ...).

The question now is, how the heck are we supposed to reconcile
differing docs which are both live on MSDN and both, on the surface,
up-to-date and "official", accurate docs? That's just unacceptable.

Thanks again,

Donnie
Willy Denoyette [MVP] wrote:

http://msdn2.microsoft.com/en-us/lib....aspxdescribes the correct behavior for all versions of the framework, theprevious documentation was simply wrong.Willy.<do*********@gmail.comwrote in messagenews:11**********************@i3g2000cwc.go oglegroups.com...| Marc,|| The workaround is, prior to calling StringBuilder.ToString(), to call| StringBuilder.Replace('\0', ' '). But the docs and the actual behavior| need to match. So I'm trying to get some "official" clarification as to| what's right and what I should expect.|| Donnie||| Marc Gravell wrote:| It looks like the docs changed:| >http://msdn.microsoft.com/library/default.asp?url=/library/en-us/cpref/html/frlrfsystemtextstringbuilderclasslengthtopic.asp| vs| >http://msdn2.microsoft.com/en-us/library/system.text.stringbuilder.length.aspx| >| I guess you would have to just find the number of spaces you are| "missing", and append via the string ctor that accepts a char and a| count (int).| >| Marc|

[donnie.hale]

Marc,

Obviously you're right. But using .Length has the advantage of giving
me other behavior I want (truncation) and keeping me from having to
calculate the actual number of spaces needed. I don't have any null
characters, my strings all end up at less than 300 characters, and I
only have to do that .Replace call once - right when I need to call
StringBuilder.ToString(). The simplicity seems like an acceptable
tradeoff.

Thanks for the feedback,

Donnie

Marc Gravell wrote:

Well, that assumes that your string doesn't include any null characters
at any other places... plus has the overhead of inspecting each
character in the builder so far, which .Append(new string(' ',
padLength)) doesn't; .ToString().PadRight(overallLength) is also an
option, but duplicates the (potentially large) string (efficiency claim
here assumes the padding is shorter than the content).

Re the docs matching, the fact that the docs have changed in line with
your observation suggests strongly that the original documentation was
wrong (or possibly that they were right, but fixing the bug would have
been a potentially breaking change, so it was preferable to change the
documentation). Either way, I believe that MSDN2 tells you what you
should expect to see, which agrees with what you are seeing. But MS
would be able to give a more definitive answer.

Marc

[Willy Denoyette [MVP]]

I feel your pain, but you should accept that documentation and software
aren't without bugs. What you can do to help the community, is simply click
the "Send comments on this topic.." at the bottom of each page and hope the
contents will be updated, I experienced some good results in doing so.

Willy.
<do*********@gmail.comwrote in message
news:11**********************@p79g2000cwp.googlegr oups.com...
| Willy,
|
| Thanks for pointing me at better docs. I was looking at
|
|
http://msdn.microsoft.com/library/de...engthtopic.asp
|
| (though I started my search for the Length property at msdn2. ...).
|
| The question now is, how the heck are we supposed to reconcile
| differing docs which are both live on MSDN and both, on the surface,
| up-to-date and "official", accurate docs? That's just unacceptable.
|
| Thanks again,
|
| Donnie
|
|
| Willy Denoyette [MVP] wrote:
| >
http://msdn2.microsoft.com/en-us/lib....aspxdescribes
the correct behavior for all versions of the framework, theprevious
documentation was simply wrong.Willy.<do*********@gmail.comwrote in
messagenews:11**********************@i3g2000cwc.go oglegroups.com...| Marc,||
The workaround is, prior to calling StringBuilder.ToString(), to call|
StringBuilder.Replace('\0', ' '). But the docs and the actual behavior| need
to match. So I'm trying to get some "official" clarification as to| what's
right and what I should expect.|| Donnie||| Marc Gravell wrote:| It looks
like the docs changed:|

>http://msdn.microsoft.com/library/default.asp?url=/library/en-us/cpref/html/frlrfsystemtextstringbuilderclasslengthtopic.asp|
vs|
http://msdn2.microsoft.com/en-us/library/system.text.stringbuilder.length.aspx|
| I guess you would have to just find the number of spaces you are| >

"missing", and append via the string ctor that accepts a char and a| count
(int).| >| Marc|
|