Question about XML XPath - C# Discussion Boards

Thanks Christian
I know what the error means what I dont understand is why its getting that error.
The code is not recursive nor it have infinite loop or something.
It just change the value of the property specified which is the size.

Any other idears?

sanicra wrote:
pd.SetValue(instance, sz);

doesnt this cause another (nested) ComponentChanged event ?

Smile | :)

Luc Pattyn

[My Articles]

Thanks Luc,
I suppose it does, so what do you suggest, how do I change a propert value when a component has changed.
What I would like to do is when you try to resize a component it will force this value (sz)
The component is a picturebox. When you resize a picturebox you can make it a square or a rectangle.
What I would like is to force the size into some value (sz) which is a computation base on some aspect ratio.

My problem is where do I change the value. I tried to put it on OnComponentChanged but it gives me that error.

Hope my problem is clear to all of you so you can help me more. Thanks

Hi,

in my experience the methods OnXxxChanged() only get fired when there actually is a
change, not when the same value gets set. To restrict a new size somehow, I use
OnResize, and that one never kept firing on me. I havent used OnComponentChanged() yet.

I see basically three solutions:

1. try using OnResize()

2. prevent an infinite call chain by having a class variable that notes whether you
are already resizing, something like:

private bool IamResizing=false;

void OnComponentChanged() {
    if (!IamResizing) {
        IamResizing=true;
        ... your stuff
        IamResizing=false;
    }
}

3. prevent an infinite call chain by temporarily removing your handler from its
delegate.

ComponentChanged-=OnComponentChanged;
    ... your stuff
ComponentChanged+=OnComponentChanged;

Hope this helps.

Smile | :)

Luc Pattyn

[My Articles]

thanks. i got it sorted out with OnReSize.
I created a class and just override the OnResize and
put my code in there.

Thank you for your ideas and help.
God bless.

hi im new to c# but i do have some experience with other languages

here the problem ive wrote a PSP Game that will allow users to make their own quizes (in pretty much plain text) but i would like to make an app to make it even easier (Console or whatever) this is what i have so far

using System;<br />
<br />
using System.Collections.Generic;<br />
using System.Text;<br />
<br />
namespace ConsoleApplication1<br />
{<br />
    class Program<br />
    {<br />
<br />
        static void Main(string[] args)<br />
        {<br />
<br />
            Console.Write("How Many Questions Do You Want In This Quiz : ");<br />
            string NOQuestions = Console.ReadLine();<br />
<br />
            Console.Write("Enter A Question : ");<br />
            string Question = Console.ReadLine();<br />
<br />
            Console.Write("How Many Answers Do You Want For This Question : ");<br />
            string NOAnswers = Console.ReadLine();<br />
<br />
            Console.Write("Enter An Answer : ");<br />
            string Answer1 = Console.ReadLine();<br />
            <br />
<br />
            Console.Write("Enter A Score : ");<br />
            string Score1 = Console.ReadLine();<br />
<br />
            Console.Write("Enter An Answer Or type No to exit the answer section : ");<br />
            string Answer2 = Console.ReadLine();<br />
            <br />
<br />
            Console.Write("Enter A Score : ");<br />
            string Score2 = Console.ReadLine();<br />
<br />
            Console.Write("Enter An Answer Or type No to exit the answer section : ");<br />
            string Answer3 = Console.ReadLine();<br />
<br />
           <br />
            if (Answer3 == "No")<br />
            {<br />
                Console.Write("Enter A Time : ");<br />
                string Time = Console.ReadLine();<br />
                Console.Write(Time + " ");<br />
                Console.Write(Question + " ");<br />
                Console.Write(Answer1 + " ");<br />
                Console.Write(Answer2 + " ");<br />
                Console.Write(Score1 + " ");<br />
                Console.Write(Score2 + " ");<br />
            }<br />
            else<br />
            {<br />
                Console.Write("Enter A Score : ");<br />
                string Score3 = Console.ReadLine();<br />
            }<br />
                <br />
                <br />
            }<br />
<br />
        }<br />
<br />
<br />
    }<br />
<br />
<br />

ok now what i need to do is to make it do either of these 2 things

1.when it asks you how many answer/question you want
i want so when the correct amount of answers has been made for it to move on to the timer
and when it done the timer create a new question and when it get to the correct amount of questions make it end

2.You type No to make it stop asking you for question or answers

here the template of a quiz i made for my app

Quiz = {<br />
{ "Question", { "Answer1", "Answer2", "Answer3"}, { Score1, Score2, Score3}, Time}<br />
}<br />
<br />
Creator = "Your Name"<br />

the brackets and speech marks must remain the same and each line is one question all the question except the last one need to have a , after it

SO COULD YOU POINT ME IN THE DIRECTION THAT I NEED TO GO THANKS

Hi
OK, first of all you need to make sure that the user has entered a number for the number of questions. int.TryParse can be used to turn a string into a number, or tell you if it can't be done. Then you want to create a loop, as in

for (int i=0;i<numquestions;++i) where="" numquestions="" is="" the="" int="" you="" created="" as="" per="" int.tryparse
{
="" any="" code="" put="" in="" here="" will="" be="" run="" numquesions="" times.
}

so,="" then="" your="" to="" get="" a="" question="" goes="" inside="" loop="" and="" runs="" number="" of="" times="" hoped.="" i'd="" create="" struct="" represent="" answer,="" list="" them="" add="" within="" loop.
=""

<div="" class="ForumSig">Christian Graus - Microsoft MVP - C++
Metal Musings - Rex and my new metal blog
"I am working on a project that will convert a FORTRAN code to corresponding C++ code.I am not aware of FORTRAN syntax" ( spotted in the C++/CLI forum )

Hello,

I have a xml document like this:

< ? xml version = " 1.0 " ? >
< Accounts >
< Account ID = " 123456 " >
< FirstName > Latheesan < / FirstName >
< SecondName > Kanes < / SecondName >
< Balance > 0 < / Balance >
< OverDraftLimit > 50 < / OverDraftLimit >
< FullAddress > My Address Here < / FullAddress >
< / Account >
< / Accounts >

What i am trying to do is select one matching document node based on my XPath expression and then when found, assign each element node's value to set of strings.

So far, this is what i was able to do:

private void searchBtn1_Click(object sender, EventArgs e)<br />
        {<br />
            try<br />
            {<br />
                string fileName = "Account_Data.xml";<br />
                XPathDocument doc = new XPathDocument(fileName);<br />
                XPathNavigator nav = doc.CreateNavigator();<br />
<br />
                // Compile Standard XPath Expression<br />
                XPathExpression expr;<br />
                expr = nav.Compile("//Account[@ID='" + accountIDInput.Text + "']");<br />
                XPathNodeIterator iterator = nav.Select(expr);<br />
<br />
                // Results<br />
                nav.MoveToFirstChild();<br />
                MessageBox.Show(nav.Value);<br />
            }<br />
            catch (Exception ex)<br />
            {<br />
                MessageBox.Show("Error : " + ex.Message);<br />
            }<br />
        }

I printed the XPath Expression result using MessageBox.Show to see what the results would be like. On the message box, i saw the entire document node and it's element nodes and their values.

How do you obtain the results after running XPath expression and assign element node's value like this:

string AccountID = nav.value;
string FirstName = nav.value;
string SecondName = nav.value;
string Balance = nav.value;
string OverDraftLimit = nav.value;
string FullAddress = nav.value;

Nevermind, i worked it out =D

private void searchBtn1_Click(object sender, EventArgs e)<br />
        {<br />
            try<br />
            {<br />
                string fileName = "Account_Data.xml";<br />
                XPathDocument doc = new XPathDocument(fileName);<br />
                XPathNavigator nav = doc.CreateNavigator();<br />
<br />
                // Compile Standard XPath Expression<br />
                XPathExpression expr;<br />
                expr = nav.Compile("//Account[@ID='" + accountIDInput.Text + "']");<br />
                XPathNodeIterator iterator = nav.Select(expr);<br />
                <br />
                iterator = nav.Select(expr);<br />
<br />
                if (iterator.MoveNext())<br />
                {<br />
                    XPathNavigator nav2 = iterator.Current.Clone();<br />
<br />
                    string accID = (nav2.GetAttribute("ID", ""));<br />
                    nav2.MoveToFirstChild();<br />
                    string firstName = (nav2.Value);<br />
                    nav2.MoveToNext();<br />
                    string lastName = (nav2.Value);<br />
                    nav2.MoveToNext();<br />
                    string currentBalance = (nav2.Value);<br />
                    nav2.MoveToNext();<br />
                    string overDraftLimit = (nav2.Value);<br />
                    nav2.MoveToNext();<br />
                    string = fullAddress = (nav2.Value);<br />
                }<br />
            }<br />
            catch (Exception ex)<br />
            {<br />
                MessageBox.Show("Error : " + ex.Message);<br />
            }<br />
        }

hi all !

i'm pretty newbie in the coding world and have a little problem that i cant find a solution

i have 2 richtextbox. the first is to write the text and the second to see it (read only)

so there is my code

<br />
<br />
private void button2_Click_1(object sender, EventArgs e)<br />
      {<br />
          DateTime dt = DateTime.Now;<br />
          string str1 = dt.ToString("H:mm:ss").PadRight(10);<br />
          string str2 = richTextBox1.Text;<br />
          string str3 = str1 + str2 + "\n";<br />
          richTextBox2.AppendText(str3);<br />
          richTextBox1.Clear();<br />

the real goal is simple, i want the time to be wrote at the start of every text add. Thats why i made it like that. My problem is the "\n" at the end of the string 3. If i dont put it, then the next text is wrote a the end of the first one. If i put it and the user finish is text and press enter then the click button, i have a empty line (witch i dont want it). The richtextbox2 gonna be print at the end and its a report to be showed to the boss as a clean copy so empty lines need to be removed.

if someone can help me

btw, sorry for my english, i know i'm bad but what can i say ? i'm talking in english like in coding Laugh | :laugh:

thanks

Um, have you tried this?

DateTime dt = DateTime.Now;<br />
this.richTextBox1.SelectedText = dt.ToString("H:mm:ss").PadRight(10);

i just tried but it give me the time after the text

i'm still working on it

thanks for the answer though Smile | :)

hi, i'm not sure anymore, i've confused myself.

i have this in a com-visible dll:

<br />
public class Interop : ITouchlibInterop<br />
    {<br />
         public virtual void fingerDown()<br />
         {<br />
             //some code here that handles the 'event'<br />
         }<br />
     }<br />

now in another file, my interface (winforms);

<br />
class Touch : Interop<br />
    {<br />
        public override void fingerDown()<br />
        {<br />
           //some new code that handles it<br />
        }<br />
    }<br />

the first class (Interop : ITouchlibInterop) is called from a c++ dll via COM. then i want my derived class - that is my interface handle the 'event' and not the com-visible dll.

now for my question:
will Touch.fingerDown() be called when Interop.fingerDown() is called?

rather have something you don't need, than need something you don't have

Hi,

Interop a=new Touch();
a.fingerDown();

will call Touch.fingerDown() although a is declared only as an Interop object.

BTW you should start public methods with an uppercase letter.

Smile | :)

Luc Pattyn

[My Articles]

thanks again for you help

rather have something you don't need, than need something you don't have

Hello guys,

i am having a problem using Delegates,
now i am working on an application where i have a label on a form and then i have a separate class in separate CS file (ie., Form1.cs and myClass.cs)

what i am trying to do : i wanted to update label1.Text every tick of a timer with the format 00:00 next tick 00:01, then next tick 00:02 and so on

so in my Class there is a timer(System.Timers.Timer/System.Threading.Timer/System.Windows.Forms.Timer) and i am trying to update the label1 in form1 using the following :

Form1 :
-----------
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;

namespace WindowsApplication2
{

public partial class Form1 : Form
{

public Form1()
{
InitializeComponent();
}
public void setlabeltext(Label lbl, String strValue)
{
lbl.Text = strValue;
}
private void Form1_Load(object sender, EventArgs e)
{
Class1 myClass = new Class1();
myClass.startCall();
}
}
}

myClass:
--------------
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
using Timers = System.Windows.Forms.Timer;

namespace WindowsApplication2
{
class Class1
{
Form1 form1 = new Form1();

Timers timoz = new Timers();

public void timoz_Tick(object sender, EventArgs e)
{
ThreadSafeSetLable(form1.label1, DateTime.Now.Subtract(DateTime.Now).ToString());
}

private void ThreadSafeSetLable(Label lbl, string value)
{
if (form1.InvokeRequired)
{

form1.Invoke(new SetString(form1.setlabeltext), new object[] { lbl, value });
}
else
{
form1.setlabeltext(lbl, value);

}
}

private delegate void SetString(Label txtBox, string strValue);

public void startCall()
{
timoz.Interval = 1000;
timoz.Start();
timoz.Tick += new EventHandler(timoz_Tick);
}
}
}

this is not working i dont know why , it compiles no problem , in the debugging the label1.text is changing to 00:00:00 but runtime i dont see that , plus the form1.InvokeRequired never gets to "true" , i do realize that i am missing something but i dont know what , can i have help on that ? thanx

T.R.

Tamer A.Rahman wrote:
Form1 form1 = new Form1();

I'm not sure what you hope this to do, but it will create a new instance of Form1, which is in no way related to the one that is visible on your screen.

Your controls should also not be made public on the class, delegates are used to avoid such nastiness. A delegate defined in class1, should call a method in form1, and pass in the string to set. The method should assign the string to the label, and class1 calls the delegate whenever it likes, via your timer or whatever.

Christian Graus - Microsoft MVP - C++
Metal Musings - Rex and my new metal blog
"I am working on a project that will convert a FORTRAN code to corresponding C++ code.I am not aware of FORTRAN syntax" ( spotted in the C++/CLI forum )

well, thank you for the reply,

i got it already Smile | :)

it was the wrong approach from the begining and i fixed it

thanks for all the help anyway Smile | :)

I am using VS2005 with SQLServer Express Edition. Select SQL statement work fine but not Insert or update. Is there something am doing wrong?

Sample insert code.
DataSet.DatabaseDataSetTableAdapters.SaleTransactionTableTableAdapter SaleTransAdapter = new DataSet.DatabaseDataSetTableAdapters.SaleTransactionTableTableAdapter();
SaleTransAdapter.Insert(7, (decimal)NetTotal, DateTime.Now);

Nana

i add the same problem with i think.

the problem is when you create the DB, it make a copy of it in your bin/debug forder and every update are in this DB

the one you create is the basic one and every time you run the debugger, he takes all the info in the basic one to overwrite the bin/debug one but the screen result show you the bin/debug DB.

so, it look like the add you made are not working

in your db explorer, create a new connection and link it to the bin/debug one then when you add something, check in this one

hope it help you !

have a good one Wink | ;)

Thank you for your help. I am afraid to say its still not working. Only select statements work after i have manually populated the database. Insert and updates still don't. i added a connection to the copy in the debug. It also has the same data as the one in the local folder. Insert still not working on that one too. I will appreciate anymore suggestions

Nana

Well thanks for your suggestion. I tried it and its still not working. Insert and update statement do not work on the database cope in the debug directory too. The select statement works if i populate the database manually. I create insert and update commands to no success. I will appreciate anymore sugestions. Thanks

Nana

You need to set insert and update commands

Well thanks for your suggestion. I tried it and its still not working. Insert and update statement do not work on the database cope in the debug directory too. The select statement works if i populate the database manually. I create insert and update commands to no success. I will appreciate anymore sugestions. Thanks

Nana

Hi

I'm currently developing a windows application in c#. I have a set of static libraries written in c++ which I used in a VC++ application. The libraries have numerous classes which would be useful. So I'd like to instantiate object of these classes in my c# code. The question is should I discard the libraries and re-write the code or can I make this into managed code or can I leave it and use it as is.

Any suggestions would be great!

Cheers