Convert or Parse - C# Discussion Boards

Re: How to read e-mails from a .NET program?

Xiangyang Liu 刘向阳12-Feb-09 9:50

Xiangyang Liu 刘向阳

12-Feb-09 9:50

Thanks, I will take a look.

My .NET Business Application Framework
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My Younger Son & His "PET"

Reading RSS from c#

Goersch123412-Feb-09 7:26

Goersch1234

12-Feb-09 7:26

Hello,

I'm trying to read a RSS from within a C# code like this (I found this example on the internet):
XmlTextReader rssReader;
XmlDocument rssDoc;
XmlNode nodeRss=null;

rssReader = new XmlTextReader( *** URL *** );
rssDoc = new XmlDocument();
rssDoc.Load(rssReader);

for (int i = 0; i < rssDoc.ChildNodes.Count; i++)
if (rssDoc.ChildNodes[i].Name == "rss")

for (int ii = 0; ii < nodeRss.ChildNodes.Count; ii++)
if (nodeRss.ChildNodes[ii].Name == "channel")
nodeChannel = nodeRss.ChildNodes[ii];

This works fine for most of the RSS I tried. But it doesn't work with this one:
http://www.klack.de/include/generateRSS.php?TYPE=TVPLANER&ID=d7fdb37979873520025e66554beb532d3065904

I get an exception on "rssDoc.Load(rssReader);": The main element is not available. (translated from german).

Does anybody know how I can fix or get around this ?

Thanks !
Georg

Re: Reading RSS from c#

EliottA12-Feb-09 8:15

EliottA

12-Feb-09 8:15

There is no RSS feed at that link?

Check out the CodeProject forum Guidelines[^]

Re: Reading RSS from c#

Goersch123412-Feb-09 8:24

Goersch1234

12-Feb-09 8:24

well, yes there is - at least FireFox can handle it as a RSS feed.

Re: Reading RSS from c#

Guffa12-Feb-09 14:40

Guffa

12-Feb-09 14:40

No, there isn't. I get a response with the length zero:

Date: Fri, 13 Feb 2009 01:37:56 GMT
Server: Apache/2.2.3 (Debian) PHP/5.2.0-8+etch11
X-Powered-By: PHP/5.2.0-8+etch11
Content-Length: 0
Content-Type: text/html; charset=UTF-8
Via: 1.1 www.klack.de
Keep-Alive: timeout=15, max=500
Connection: Keep-Alive

Despite everything, the person most likely to be fooling you next is yourself.

Re: Reading RSS from c#

emiaj12-Feb-09 8:25

emiaj

12-Feb-09 8:25

http://www.codeproject.com/info/search.aspx?artkw=rss[^]

Jaime Febres
The worst blog in the world

Re: Reading RSS from c#

Goersch123412-Feb-09 8:29

Goersch1234

12-Feb-09 8:29

I tried "RSS 2.0 Framework" but it gets into the same trouble. That's why
I tried to run something more simple - with the same result.

Convert or Parse

Lodeclaw12-Feb-09 6:43

Lodeclaw

12-Feb-09 6:43

I was told that the most common method to convert a value is to use the Parse method, however it only works with strings, as you all know...

So I was wondering, then: if you're converting a non-string value to another non-string, is it better/more efficient to use for example...

Convert.ToInt32(value);
or
int.Parse(value.ToString());

Thanks guys!

Re: Convert or Parse

Luc Pattyn12-Feb-09 6:56

Luc Pattyn

12-Feb-09 6:56

Hi,

it depends on the Type of your value:

if value is a string, then value.ToString() is redundant, and both Convert and int.Parse would behave identically (in fact one is calling the other).

if value is some kind of integer to begin with, Convert.ToInt32() is much faster, since no conversion from integer to string, and no conversion from string to int are involved.

if value is something else (a DateTime, a user-defined type, ...) Convert will not accept it,
whereas the value.ToString() result may or may not look like an integer, and be acceptable to int.Parse

Smile | :)

Luc Pattyn [Forum Guidelines] [My Articles]

- before you ask a question here, search CodeProject, then Google
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modified on Sunday, June 12, 2011 8:02 AM

Re: Convert or Parse

akidan12-Feb-09 7:14

akidan

12-Feb-09 7:14

Luc summed it up well, but I just wanted to add one other non-obvious difference.

With value = null;
Convert.ToInt32(value) returns 0
int.Parse(value.ToString()) throws NullReferenceException.
int.Parse(value) throws ArgumentNullException. (if value is String)

Re: Convert or Parse

freakyit12-Feb-09 9:18

freakyit

12-Feb-09 9:18

hi,

look at the int.TryParse(object,out bool) functionality.
The boolean value stands up for true (parseable) and false(not parseable) about trying to parse the value. There will be no exception raised. if you want to use int.Parse instead of TryParse you need to catch the exception with try catch..

bless Smile | :)

Re: Convert or Parse

PIEBALDconsult12-Feb-09 12:02

PIEBALDconsult

12-Feb-09 12:02

In my opinion the only worthwhile member of Convert is System.Convert.ChangeType, will that do what you want?

Otherwise, maybe a simple cast is what you want?

Or, if it's a type of your own creation, perhaps an implicit conversion operator?

You would have to give us more information.

Re: Convert or Parse

Mycroft Holmes12-Feb-09 14:15

Mycroft Holmes

12-Feb-09 14:15

Hijack

If you have 2 classes that are identical (set of credentials) can you use System.Convert.ChangeType to convert one to the other?

Never underestimate the power of human stupidity
RAH

Re: Convert or Parse

Guffa12-Feb-09 15:06

Guffa

12-Feb-09 15:06

The most common method to convert a non-string value to an int is implicit or explicit casting. Example:

// implicit casting:
byte b = 42;
int answer = b;

// explicit casting:
double d = 42.0;
int answer = (int)d;

Despite everything, the person most likely to be fooling you next is yourself.

ASP file not being able to to find a class that is in the same namespace.

Steve Holdorf12-Feb-09 6:40

Steve Holdorf

12-Feb-09 6:40

I have an ASP file and a Customer class both in the same namespace. When I compile I receive the error: The type or namespace name 'Customer' could not be found (are you missing a using directive or an assembly reference?). I have checked and the asp page

Inherits="PopupApplication.InitDialog"

And the Customer was created in that namespace and has that namespace in the class file. Can anyone help?

Thanks,

Steve

Re: ASP file not being able to to find a class that is in the same namespace.

Calin Tatar12-Feb-09 11:59

Calin Tatar

12-Feb-09 11:59

Make sure your class is decorated with "public".
Also, you may try to move it in App_Code folder.

Calin

pivot table

Dushan12312-Feb-09 6:10

Dushan123

12-Feb-09 6:10

is there is any free pivot chart Controller for visual studio

Dushan Perera

Need to restric Base Method on Derive and Access on Other Namespace hierarchy class.

Tarini Singh12-Feb-09 5:54

Tarini Singh

12-Feb-09 5:54

Hi Team,

Required functional is to access the Base class Method itself on other hierarchy class but need to restrict the base class method on derive class.

For Example,

Base Class B --------> Having Static Method M

Derive D from B 
 Need to restrict the access of Method M through D but should be accessible  through B.

Can anybody help me out.

Thanks in Advance
Tarun Singh

Re: Need to restric Base Method on Derive and Access on Other Namespace hierarchy class.

musefan12-Feb-09 6:00

musefan

12-Feb-09 6:00

maybe use the sealed keyword, im not sure thou

no, dont think so lol... try 'explicit' keyword instead

If only MySelf.Visible was more than just a getter...

A person can produce over 5 times there own body weight in excrement each year... please re-read your questions before posting

Re: Need to restric Base Method on Derive and Access on Other Namespace hierarchy class.

DaveyM6912-Feb-09 6:19

DaveyM69

12-Feb-09 6:19

explicit is for overloading conversion operators.

Dave
BTW, in software, hope and pray is not a viable strategy. (Luc Pattyn)
Visual Basic is not used by normal people so we're not covering it here. (Uncyclopedia)

Re: Need to restric Base Method on Derive and Access on Other Namespace hierarchy class.

Tarini Singh12-Feb-09 23:26

Tarini Singh

12-Feb-09 23:26

No, Not Fulfill the functionality.

Re: Need to restric Base Method on Derive and Access on Other Namespace hierarchy class.

DaveyM6912-Feb-09 6:18

DaveyM69

12-Feb-09 6:18

Not sure you can.

The best I can think of is to mark D's M as internal new, that way it won't be visible outside that particular assembly but B's M will.

Dave
BTW, in software, hope and pray is not a viable strategy. (Luc Pattyn)
Visual Basic is not used by normal people so we're not covering it here. (Uncyclopedia)

Re: Need to restric Base Method on Derive and Access on Other Namespace hierarchy class.

ABitSmart12-Feb-09 15:34

ABitSmart

12-Feb-09 15:34

One way I can see doing this is by adding a level of hierarchy,

Base Class B //Not having Method M, but all others

Derived Class B_With_M //Deriving from B but and having Method M (as protected to restrict it to only derived class)

Derived Class D //Deriving from B, this will be your class with Base as B(through hierarchy) and not having M.

All other classes whom you want to give access to M will derive from B_With_M and not from B.

problem with é, à, è

abbd12-Feb-09 5:39

abbd

12-Feb-09 5:39

Hello,
when reading a text file, the letters having accents, they appear square caps in a message box, how can we keep the same letters? thank you verry much.

Re: problem with é, à, è

musefan12-Feb-09 5:46

musefan

12-Feb-09 5:46

its down to the encoding of the text, as far as i know you cant change that with the message box directly but maybe it can be set in the system

If only MySelf.Visible was more than just a getter...

A person can produce over 5 times there own body weight in excrement each year... please re-read your questions before posting

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