473,938 Members | 25,039 Online
Bytes | Software Development & Data Engineering Community
+ Post

Home Posts Topics Members FAQ

XPathNavigator. ValueAsBoolean - no exception

Hi;

How can I tell if I can call XPathNavigator. ValueAsBoolean safely - without
throwing an exception. I want to take one course of action if the value can
be interpreted as a boolean.

But I din't want to do it using try/catch - I think having exceptions be
thrown when the code is operating normally is very bad - both from a
performance point of view and because it signifiys an error.

--
thanks - dave
Nov 12 '05 #1
6 1415
Hi dave,

Currently we are looking for someone to help you on this issue, we will
reply to you ASAP. Thanks for your understanding.

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.

Nov 12 '05 #2
David Thielen wrote:
How can I tell if I can call XPathNavigator. ValueAsBoolean safely - without
throwing an exception. I want to take one course of action if the value can
be interpreted as a boolean.

But I din't want to do it using try/catch - I think having exceptions be
thrown when the code is operating normally is very bad - both from a
performance point of view and because it signifiys an error.


I don't think XPathNavigator provides such functionality. The idea is
that when using ValueAsXXX methods you can be sure about node type, e.g.
because XML is valid.
As a workaround you can use Boolean.TryPars e method, which doesn't throw
an exception when values cannot be converted to boolean:

if (Boolean.TryPar se(navigator.Va lue, out myvalue))
//parsed ok
else
//not boolean value

--
Oleg Tkachenko [XML MVP, MCAD]
http://www.xmllab.net
http://blog.tkachenko.com
Nov 12 '05 #3
Hello;

My problem is customers can throw any xml at us and we have an if (Value is
Boolean) piece of logic. I think your solution will fix it - will post back
either way.

--
thanks - dave
"Oleg Tkachenko [MVP]" wrote:
David Thielen wrote:
How can I tell if I can call XPathNavigator. ValueAsBoolean safely - without
throwing an exception. I want to take one course of action if the value can
be interpreted as a boolean.

But I din't want to do it using try/catch - I think having exceptions be
thrown when the code is operating normally is very bad - both from a
performance point of view and because it signifiys an error.


I don't think XPathNavigator provides such functionality. The idea is
that when using ValueAsXXX methods you can be sure about node type, e.g.
because XML is valid.
As a workaround you can use Boolean.TryPars e method, which doesn't throw
an exception when values cannot be converted to boolean:

if (Boolean.TryPar se(navigator.Va lue, out myvalue))
//parsed ok
else
//not boolean value

--
Oleg Tkachenko [XML MVP, MCAD]
http://www.xmllab.net
http://blog.tkachenko.com

Nov 12 '05 #4
:(

I am in J# and I can't call TryParse - I assume because java does not
support ref parameters.

--
thanks - dave
"Oleg Tkachenko [MVP]" wrote:
David Thielen wrote:
How can I tell if I can call XPathNavigator. ValueAsBoolean safely - without
throwing an exception. I want to take one course of action if the value can
be interpreted as a boolean.

But I din't want to do it using try/catch - I think having exceptions be
thrown when the code is operating normally is very bad - both from a
performance point of view and because it signifiys an error.


I don't think XPathNavigator provides such functionality. The idea is
that when using ValueAsXXX methods you can be sure about node type, e.g.
because XML is valid.
As a workaround you can use Boolean.TryPars e method, which doesn't throw
an exception when values cannot be converted to boolean:

if (Boolean.TryPar se(navigator.Va lue, out myvalue))
//parsed ok
else
//not boolean value

--
Oleg Tkachenko [XML MVP, MCAD]
http://www.xmllab.net
http://blog.tkachenko.com

Nov 12 '05 #5
TryParse method is only available in .NET framework 2.0. Besides, there is
no way to judge whether a value is boolean without try to parse it and gets
exception.

http://msdn2.microsoft.com/en-us/library/khxs34ek

Kevin Yu
=======
"This posting is provided "AS IS" with no warranties, and confers no
rights."

Nov 12 '05 #6
That's what I was afraid of.

--
thanks - dave
"Kevin Yu [MSFT]" wrote:
TryParse method is only available in .NET framework 2.0. Besides, there is
no way to judge whether a value is boolean without try to parse it and gets
exception.

http://msdn2.microsoft.com/en-us/library/khxs34ek

Kevin Yu
=======
"This posting is provided "AS IS" with no warranties, and confers no
rights."

Nov 12 '05 #7

This thread has been closed and replies have been disabled. Please start a new discussion.

Similar topics

1
3386
by: Craig Pearson | last post by:
Hi My function receives an XPathNavigator object. From here I need to build a DataSet to load into SQL Server (using SQLXML adaptor). Does anyone have an idea on the most efficient way to convert the XPathNavigator into a DataSet? Here is what I have at the moment: void function DoSomething( string xmlSchemeFile, System.Xml.XPath.XPathNavigator nav ) {
7
4099
by: David Thielen | last post by:
Hi; Is there a way from an XPathNavigator object to get an xpath string that will, when used in a Select(xpath) on the underlying base/root XPathNavigator return the same XPathNavigator? In other words, I initially create an XPathNavigator for my entire xml document. To get an XPathNavigator object who's root is a given node in the original xml document, there is a unique xpath that will return that node. The unique xpath could have,...
1
1860
by: David Thielen | last post by:
Hi; How do I handle the following: XPathNavigator nav = ...; String str = nav.SelectSingleNode("floats/@ok").Value; // works fine - returns 1.3 nav.SelectSingleNode("floats/@ok == 1.3"); // throws an exception
12
3983
by: David Thielen | last post by:
Hi; I have an element: <space> </space> When I call SelectSingleNode() on it, the InnerXml is a 0 length String, not a String containing 1 space. Any ideas?
2
2901
by: JSheble | last post by:
I'm integrating with a customer application, and in their assembly, when I call a method it returns data to us as an XPathNavigator object. I can parse the various elements I need out of this object with no problem, but what I cannot seem to do is get at the actual XML string itself. For accountability, tracking, auditing, and logging, I need to save the XML as an XML file in an archive folder, but there doesn't seem to be any way of...
4
17550
by: Andy Fish | last post by:
Hi, I can't figure out for the life of me how to select nodes using a namespace in XpathNavigator. For example: XPathDocument doc = new XPathDocument("file.xml"); XPathNavigator nav = doc.CreateNavigator(); XPathNodeIterator itr = nav.Select("/foo:bar"); Throws the exception "Namespace Manager or XsltContext needed. This query
11
6486
by: ericms | last post by:
Can anybody show me how to insert a CDATA section using XPathNavigator ? I have tried the follwing with no luck: XmlDocument docNav = new XmlDocument(); docNav.LoadXml(xmlString); XPathNavigator nav = docNav.CreateNavigator(); XmlDocument doc = new XmlDocument(); doc.LoadXml("<DocumentData></DocumentData>"); XmlElement elem = doc.CreateElement(currentNodeName);
4
4412
by: Bruce Sandeman | last post by:
Hi, Does anyone know how to serialize an XPathNavigator object? I have tried the following but it moans that the xpn does not have a parameterless constructor. XPathNavigator xpn = e.Source.SelectSingleNode("/ns1:Invoice/ns1:InvoiceDetail/ns1:Lines/ns1:Line/ns1:Matches/ns1:Match/ns1:SubLedger", this.NamespaceManager); XmlSerializer x = new XmlSerializer(xpn.GetType()); StringWriter tw = new StringWriter();
2
4552
by: =?Utf-8?B?Tm9yZW1hYw==?= | last post by:
Hi. Using VS2005, .NET 2.0. I have an xml document that I want to go through and set the values on attributes of elements. The elements are complex types defined in my schema (xsd) files. I can iterate the document and get my XmlType and XmlBaseType values just fine. However, as soon as I call SetValue to write to an attribute, the
0
10134
marktang
by: marktang | last post by:
ONU (Optical Network Unit) is one of the key components for providing high-speed Internet services. Its primary function is to act as an endpoint device located at the user's premises. However, people are often confused as to whether an ONU can Work As a Router. In this blog post, we’ll explore What is ONU, What Is Router, ONU & Router’s main usage, and What is the difference between ONU and Router. Let’s take a closer look ! Part I. Meaning of...
0
9963
by: Hystou | last post by:
Most computers default to English, but sometimes we require a different language, especially when relocating. Forgot to request a specific language before your computer shipped? No problem! You can effortlessly switch the default language on Windows 10 without reinstalling. I'll walk you through it. First, let's disable language synchronization. With a Microsoft account, language settings sync across devices. To prevent any complications,...
0
11524
Oralloy
by: Oralloy | last post by:
Hello folks, I am unable to find appropriate documentation on the type promotion of bit-fields when using the generalised comparison operator "<=>". The problem is that using the GNU compilers, it seems that the internal comparison operator "<=>" tries to promote arguments from unsigned to signed. This is as boiled down as I can make it. Here is my compilation command: g++-12 -std=c++20 -Wnarrowing bit_field.cpp Here is the code in...
0
11106
jinu1996
by: jinu1996 | last post by:
In today's digital age, having a compelling online presence is paramount for businesses aiming to thrive in a competitive landscape. At the heart of this digital strategy lies an intricately woven tapestry of website design and digital marketing. It's not merely about having a website; it's about crafting an immersive digital experience that captivates audiences and drives business growth. The Art of Business Website Design Your website is...
1
11289
by: Hystou | last post by:
Overview: Windows 11 and 10 have less user interface control over operating system update behaviour than previous versions of Windows. In Windows 11 and 10, there is no way to turn off the Windows Update option using the Control Panel or Settings app; it automatically checks for updates and installs any it finds, whether you like it or not. For most users, this new feature is actually very convenient. If you want to control the update process,...
0
9857
agi2029
by: agi2029 | last post by:
Let's talk about the concept of autonomous AI software engineers and no-code agents. These AIs are designed to manage the entire lifecycle of a software development project—planning, coding, testing, and deployment—without human intervention. Imagine an AI that can take a project description, break it down, write the code, debug it, and then launch it, all on its own.... Now, this would greatly impact the work of software developers. The idea...
0
7384
by: conductexam | last post by:
I have .net C# application in which I am extracting data from word file and save it in database particularly. To store word all data as it is I am converting the whole word file firstly in HTML and then checking html paragraph one by one. At the time of converting from word file to html my equations which are in the word document file was convert into image. Globals.ThisAddIn.Application.ActiveDocument.Select();...
0
6295
by: adsilva | last post by:
A Windows Forms form does not have the event Unload, like VB6. What one acts like?
1
4905
by: 6302768590 | last post by:
Hai team i want code for transfer the data from one system to another through IP address by using C# our system has to for every 5mins then we have to update the data what the data is updated we have to send another system

By using Bytes.com and it's services, you agree to our Privacy Policy and Terms of Use.

To disable or enable advertisements and analytics tracking please visit the manage ads & tracking page.