Still celebrating National IT Professionals Day with 3 months of free Premium Membership. Use Code ITDAY17

x
?
Solved

Editing a single value in XML file from a windows Form application c#

Posted on 2010-08-19
4
Medium Priority
?
475 Views
Last Modified: 2013-12-17
Hi,

Am using VS2008, I've a c# windows form app and I am loading info from my XML file into various text boxes on the form. (this bit is working) I need to be able to edit one of the text boxes and have this change updated to the XML file. I've had a go at this but, the file doesn't change. (I'm very new to xml, 1 day) My XML file format is similar to the following:


<?xml version="1.0" encoding="utf-8"?>
<Lessons>
  <Lesson ID =" 01">
    <ButtonName>btnLesson01</ButtonName>
    <Title>Lesson One</Title>
    <Description>This will recreate etc etc </Description>
    <Points>1</Points>
  </Lesson>
  <Lesson ID =" 02">
    <ButtonName>btnLesson02</ButtonName>
    <Title>Lesson Two</Title>
    <Description>This will etc etc </Description>
    <Points>9</Points>
  </Lesson>
  <Lesson ID =" 03">
    <ButtonName>btnLesson03</ButtonName>
   <Title>Lesson Three</Title>
    <Description>This will etc etc </Description>
    <Points>4</Points>
  </Lesson>
  <Lesson ID ="04">
    <ButtonName>btnLesson04</ButtonName>
   <Title>Lesson Four</Title>
    <Description>This will etc etc </Description>
    <Points>10</Points>
  </Lesson>
</Lessons>



My attached code isn't updating the Points element though.
lessonID   in   XmlNode nodeToEdit = doc.SelectSingleNode("/Lessons/Lesson[@ID="+lessonID+"]");    is a string which I assign a value to elsewhere.

Any idea? Thanks





XmlReader reader = XmlReader.Create(FILE_NAME);
            XmlDocument doc = new XmlDocument();
            doc.Load(reader);
       
            XmlNode nodeToEdit = doc.SelectSingleNode("/Lessons/Lesson[@ID="+lessonID+"]");
              if (nodeToEdit != null)
              {
                  nodeToEdit["Points"].InnerText = txtPoints.Text;
                  
              }
              doc.Save("FILE_NAME");
              doc = null;

Open in new window

0
Comment
Question by:gemky
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
4 Comments
 
LVL 5

Accepted Solution

by:
tvPrasad earned 750 total points
ID: 33477918
Hi,
Are you supplying a valid path file name in save ?
 You should supply path i.e.. C:\Lessons.xml
  doc.Save(@"C:\Lessons.xml");

You can check the xml file for updates once executed.
0
 
LVL 64

Assisted Solution

by:Fernando Soto
Fernando Soto earned 750 total points
ID: 33477976
Hi gemky;

I tested your code without modifying it and it works fine, are you sure it is not updating the correct Lesson ID node, are you looking at the wrong Lesson ID?

Fernando
0
 
LVL 27

Expert Comment

by:nmarun
ID: 33478161
0
 

Author Closing Comment

by:gemky
ID: 33483703
Thanks for your help.   I didn't realise this was actually saving as I was only looking at Lessons.xml in the directory. I hadn't spotted a new file called FILENAME in the directory.

What I was doing was silly, I have

 const string FILE_NAME = "Lessons.xml";

and in the save I had
doc.Save("FILE_NAME");  

doc.Save(FILE_NAME);

Thanks everyone
0

Featured Post

Free learning courses: Active Directory Deep Dive

Get a firm grasp on your IT environment when you learn Active Directory best practices with Veeam! Watch all, or choose any amount, of this three-part webinar series to improve your skills. From the basics to virtualization and backup, we got you covered.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

In my previous two articles we discussed Binary Serialization (http://www.experts-exchange.com/A_4362.html) and XML Serialization (http://www.experts-exchange.com/A_4425.html). In this article we will try to know more about SOAP (Simple Object Acces…
The Client Need Led Us to RSS I recently had an investment company ask me how they might notify their constituents about their newsworthy publications.  Probably you would think "Facebook" or "Twitter" but this is an interesting client.  Their cons…
This tutorial will teach you the special effect of super speed similar to the fictional character Wally West aka "The Flash" After Shake : http://www.videocopilot.net/presets/after_shake/ All lightning effects with instructions : http://www.mediaf…
How to fix incompatible JVM issue while installing Eclipse While installing Eclipse in windows, got one error like above and unable to proceed with the installation. This video describes how to successfully install Eclipse. How to solve incompa…

688 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question