Re: Xml database - C# Discussion Boards

14-Feb-10 6:48

this taken from another forum i'm on, however they dont seem to have an answer.It is 2 posts i have put into this 1 post to show the progression.

POST 1

Hello, i'm trying to create an XML database to hold names.

It's for a game based on film making. I have 3 forms 1 main form 1 for naming the film 1 for archives (to view what films you have made in the past)

Basically in the name the film form you add the name into a text box, to avoid using a database orginally as i don't understand them fully i used a list.

NAMING FORM

using System;<br />
using System.Collections.Generic;<br />
using System.ComponentModel;<br />
using System.Data;<br />
using System.Drawing;<br />
using System.Linq;<br />
using System.Text;<br />
using System.Windows.Forms;<br />
<br />
namespace Pmanager<br />
{<br />
    public partial class Shoot : Form<br />
    {<br />
        string moviename;<br />
        public List<string> FilmNames = new List<string>();<br />
        <br />
        public Shoot()<br />
        {<br />
            InitializeComponent();<br />
            <br />
        }<br />
<br />
        private void textBox1_TextChanged(object sender, EventArgs e)<br />
        {<br />
            moviename = textBox1.Text;<br />
            <br />
            <br />
        }<br />
<br />
        private void button1_Click(object sender, EventArgs e)<br />
        {<br />
            listmethod();<br />
            foreach (string Item in FilmNames)<br />
            {<br />
                MessageBox.Show(Item + "\r\n"); // put this in to check if the list was storing between forms<br />
            }<br />
            <br />
        }<br />
<br />
        public void listmethod()<br />
        {<br />
            <br />
            FilmNames.Add(moviename);<br />
<br />
        }<br />
    }<br />
}

ARCHIVES

using System;<br />
using System.Collections.Generic;<br />
using System.ComponentModel;<br />
using System.Data;<br />
using System.Drawing;<br />
using System.Linq;<br />
using System.Text;<br />
using System.Windows.Forms;<br />
<br />
namespace Pmanager<br />
{<br />
    public partial class Archieves : Form<br />
    {<br />
        Shoot shoot = new Shoot();<br />
        public Archieves()<br />
        {<br />
            InitializeComponent();<br />
        }<br />
<br />
        private void Archieves_Load(object sender, EventArgs e)<br />
        {<br />
            <br />
        }<br />
<br />
        private void textBox1_TextChanged(object sender, EventArgs e)<br />
        {<br />
            foreach (string Item in shoot.FilmNames)<br />
            {<br />
                textBox1.Text += Item + "\r\n";<br />
            }<br />
<br />
        }<br />
<br />
      <br />
    }<br />
}

However it became apparent that why i try to view this list in the archives it wont store the data and writes over it because I am recalling it. So I believe I need a database. I chose to use XML as i dont seem to understand sql to well

in my program main I'm creating a new XML database, this works fine. But i'm not really sure how to store the film names from the txtbox input in naming and displaying in archives.

So I'm unsure where to go, documentation I've looked at doesn't really give an indication, so if anyone could help or if there is a way of storing the list between forms it would be much appreciated.

using System;<br />
using System.Collections.Generic;<br />
using System.Linq;<br />
using System.Windows.Forms;<br />
using System.Xml;<br />
namespace Pmanager<br />
{<br />
    static class Program<br />
    {<br />
        /// <summary><br />
        /// The main entry point for the application.<br />
        /// </summary><br />
        [STAThread]<br />
        static void Main()<br />
        {<br />
            Application.EnableVisualStyles();<br />
            Application.SetCompatibleTextRenderingDefault(false);<br />
            Application.Run(new Main());<br />
            XmlTextWriter xmlWriter = new XmlTextWriter("database.xml", System.Text.Encoding.UTF8);<br />
            xmlWriter.Formatting = Formatting.Indented;<br />
            xmlWriter.WriteProcessingInstruction("xml", "version='1.0' encoding='UTF-8'");<br />
            xmlWriter.WriteStartElement("Root");<br />
            xmlWriter.Close();<br />
        }<br />
    }<br />
}

POST 2

Ok so i started working on xml databases and I got one working that both writes and reads, However it will only write or read 1 field and any added fields on top will overwrite the preceding one.I know this is because I am asking it to only write 1 xml string "ID" so i tried to add a list into the equation and now i'm fully stuck.

using System;<br />
using System.Collections.Generic;<br />
using System.ComponentModel;<br />
using System.Data;<br />
using System.Drawing;<br />
using System.Linq;<br />
using System.Text;<br />
using System.Windows.Forms;<br />
using System.Xml;<br />
<br />
namespace WindowsFormsApplication1<br />
{<br />
    public partial class Form1 : Form<br />
    {<br />
        string ID = ("ID");<br />
<br />
<br />
        public Form1()<br />
        {<br />
            InitializeComponent();<br />
        }<br />
<br />
        private void Form1_Load(object sender, EventArgs e)<br />
        {<br />
            XmlTextReader reader = new XmlTextReader(Application.StartupPath + @"\\xmldata.xml");<br />
            while (reader.Read())<br />
            {<br />
                switch (reader.NodeType)<br />
                {<br />
                    case XmlNodeType.Text:<br />
                        textBox2.Text = reader.Value;<br />
                        break;<br />
<br />
                }<br />
            }<br />
        }<br />
<br />
        private void button1_Click(object sender, EventArgs e)<br />
        {<br />
            string sStartupPath = Application.StartupPath;<br />
            XmlTextWriter objXmlTextWriter = new XmlTextWriter(sStartupPath + @"\\xmldata.xml", null);<br />
            objXmlTextWriter.Formatting = Formatting.Indented;<br />
            objXmlTextWriter.WriteStartDocument();<br />
            objXmlTextWriter.WriteStartElement(ID);<br />
            objXmlTextWriter.WriteString(textBox1.Text);<br />
            objXmlTextWriter.WriteEndElement();<br />
            objXmlTextWriter.WriteEndDocument();<br />
            objXmlTextWriter.Flush();<br />
            objXmlTextWriter.Close();<br />
        }<br />
<br />
        private void textBox2_TextChanged(object sender, EventArgs e)<br />
        {<br />
<br />
        }<br />
<br />
    }<br />
}

Dan Mos14-Feb-10 7:12

14-Feb-10 7:12

My head hurts Big Grin | :-D

antrock10114-Feb-10 7:14

14-Feb-10 7:14

hahah yeah sorry its a bit confusing, list wouldn't work, then the first xml bit was me trying to get xml to work and the second post was xml working but only adding once to the database

Dan Mos14-Feb-10 7:23

14-Feb-10 7:23

antrock101 wrote:
private void button1_Click(object sender, EventArgs e)
{
string sStartupPath = Application.StartupPath;
XmlTextWriter objXmlTextWriter = new XmlTextWriter(sStartupPath + @"\\xmldata.xml", null);
objXmlTextWriter.Formatting = Formatting.Indented;
objXmlTextWriter.WriteStartDocument();
objXmlTextWriter.WriteStartElement(ID);
objXmlTextWriter.WriteString(textBox1.Text);
objXmlTextWriter.WriteEndElement();
objXmlTextWriter.WriteEndDocument();
objXmlTextWriter.Flush();
objXmlTextWriter.Close();
}

well that is because each time you click the button1 you create a new xmlFile, you write the
start document and everything.

you're not adding to the existing one but creating a new one.

Also, try using XDocument it rocks your DOM world at least it did for me.

antrock10114-Feb-10 7:26

14-Feb-10 7:26

ah i see i thought i was just writing to the document instead of rewriting i presume the lines

XmlTextWriter objXmlTextWriter = new XmlTextWriter(sStartupPath + @"\\xmldata.xml", null);
objXmlTextWriter.Formatting = Formatting.Indented;
objXmlTextWriter.WriteStartDocument();

are coursing this, sorry i'm rather confused on xml databases having never used databases at all

Dan Mos14-Feb-10 7:40

14-Feb-10 7:40

no need to apologise. All of us were newbies at some point on different technologies.
Glad I could help

antrock10114-Feb-10 7:50

14-Feb-10 7:50

are there any xdocument tutorials the official documentation isn't very clear

Dan Mos14-Feb-10 7:58

14-Feb-10 7:58

here a couple:1
2 , 3
and google will give a lot of others

Not Active14-Feb-10 9:23

Not Active

14-Feb-10 9:23

LINQ to XML[^]

I know the language. I've read a book. - _Madmatt

Keith Barrow14-Feb-10 9:58

Keith Barrow

14-Feb-10 9:58

Your post is too long to read thoroughly, so prior apologies if I have misunderstood what you are asking for.

IMO:

1. XML is not suited to, nor is it meant for database use, it is a structured way of storing data.
2. If you must use XML, reasearch serialization on here or Google. It allows you to to convert XML files into object instances without all that TextReader stuff.

Antoine de Saint-Exupery: Perfection is achieved, not when there is nothing more to add, but when there is nothing left to take away.

antrock10114-Feb-10 10:00

14-Feb-10 10:00

thanks for the opinion, It seemed the easiest to work with database wise. I could never understand sql connection and reading and writing data no matter what i've read. It's a pain really because a real database would be more useful

Keith Barrow14-Feb-10 10:09

Keith Barrow

14-Feb-10 10:09

antrock101 wrote:
I could never understand sql connection and reading and writing data no matter what i've read.

This is a great opportunity to learn. From your post it looks like you will end up doing more work by trying to use XML than a database.
http://www.connectionstrings.com/[^] has listings of the most common connection strings. The connection and other SQL objects have about the same level of complexity as the XML stuff, so you'll be able to get to grips with it. Additionally there is LINQ to SQL and LINQ to entities that can help make the database world onto the code world.

Also XML is NOT a database and shouldn't be used as one, you have to do all the work making sure the data integrity is kept. Many projects fail because, although initially easier, using XML is much harder work in the longer term for everything except simpler, non-relational data.

Antoine de Saint-Exupery: Perfection is achieved, not when there is nothing more to add, but when there is nothing left to take away.

antrock10114-Feb-10 11:39

use only 2 digis in simple precision

14-Feb-10 11:39

the actual connection isn't an issue as visual has an in built connector i think, however i cant find tutorial on reading and writing the data in the database table without just dragging it onto a form

using webcam

naghoumeh1414-Feb-10 6:26

naghoumeh14

14-Feb-10 6:26

i want to turn on the webcam by clicking a button btturnwebcam then i want the picture to be shown in a picturebox webcampic then i want to take a photo by clicking anther button btcapture so how do i do this ? i have to note here that i have already imported the webcamcapture tool

naghoumeh1414-Feb-10 6:21

naghoumeh14

14-Feb-10 6:21

suppose a float f and if i am intrested only in using this float but having only 2 digits after the dot so what i want to do is to delete the remaining digits .. so how do i do this?

Re: use only 2 digis in simple precision

Dan Mos14-Feb-10 6:36

Re: use only 2 digis in simple precision

14-Feb-10 6:36

1) You could use Math.Round(number,2);

2) You could use the decimal type

3) If the number is in a textbox replace it with numericUpDown and specify the number of digits

Luc Pattyn14-Feb-10 6:59

Luc Pattyn

14-Feb-10 6:59

MDL=>Moshu wrote:
If the number is in a textbox replace it with numericUpDown and specify the number of digits

one can paste anything into a editable Control, so that won't cut it.

Smile | :)

Luc Pattyn [Forum Guidelines] [Why QA sucks] [My Articles]

Re: use only 2 digis in simple precision

Dan Mos14-Feb-10 7:05