Design Question (Class vs Structs) - C# Discussion Boards

Not Active1-Sep-09 8:53

Not Active

1-Sep-09 8:53

Just a guess, but are you sure all of the characters in the name can be converted to int?

only two letters away from being an asset

DaveyM691-Sep-09 9:06

DaveyM69

1-Sep-09 9:06

How can a character in a name be converted to an int?

Anyway - this will handle it using the TryParse method, though I suspect you're going to spend most of your time in the else block.

int converted;
if(Int32.TryParse(arrayOfLastNames[i], out converted)
{
    convertedLastName[i] = converted;
}
else
{
    // Do what you need to here
}

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)
Why are you using VB6? Do you hate yourself? (Christian Graus)

Re: Sorting strings [modified]

dan!sh 1-Sep-09 9:09

dan!sh

1-Sep-09 9:09

Int32.Parse would work with char and not strings. i.e. (char)'A' will be converted to its ASCII equivalent but (string)"A" will not. You will need to get each character of the last name and then convert.

AFAIK .Net uses UTF8 encoding to store strings, probably that is the reason it is not working now.

It's not necessary to be so stupid, either, but people manage it. - Christian Graus, 2009 AD

gamer11271-Sep-09 9:11

gamer1127

1-Sep-09 9:11

Uggh...What was I thinking?! My fault guys..wrong question..I was thinking about the type of an ASCII code.

So, is there a way to convert all the string into an ASCII code? I was thinking of converting all of the string to ASCII code because I think it's a good way to do to sort using radix sort just like what i said above.

modified on Tuesday, September 1, 2009 3:40 PM

dan!sh 1-Sep-09 9:49

dan!sh

1-Sep-09 9:49

1. Why can't you use Array.Sort method?
2. AFAIK the number of recursions depend upon the maximum number digits in the numbers. Hence, if you have last names like MacGhilleseatheanaich[^], I wonder how many iterations it would take.

To convert string to ASCII equivalent, you can use following code:

System.Text.Encoding encASCII= System.Text.Encoding.ASCII;
Byte[] stringBytes = encASCII.GetBytes(yourString);

It's not necessary to be so stupid, either, but people manage it. - Christian Graus, 2009 AD

gamer11271-Sep-09 10:02

gamer1127

1-Sep-09 10:02

The reason why i can't use Array.Sort() is because we're trying to implement all that we discussed about file organization and data structure etc, and because we discussed some sorting algorithms we'll be implementing radix sort. If we were not obliged to use radix sort, I would be eager to use Array.Sort and finish the program easily. Sigh | :sigh:

Design Question (Class vs Structs)

PIEBALDconsult1-Sep-09 11:21

PIEBALDconsult

1-Sep-09 11:21

They're already in ASCII.

But if you want to waste bits by using int (32 bits) rather that char (16 bit), you can cast the chars to ints.

foreach ( char ch in s )
{
    int i = (int) ch ;
 
...
}

student_rhr1-Sep-09 8:00

student_rhr

1-Sep-09 8:00

Hi Everyone,

I have a "one to many" sort of situation. I am using a Key to get subset data. I started out using a class like this:

<code>
public class Contract
{
    public int ContractID {get;set;}
    public int CustomerID {get;set;}
    public string CustomerName {get;set;}
    public string Organization {get;set;}
    public int TermsID {get;}
}
//Then data mapper
public class ContractDataMapper
{
    public static List<Contract> GetContractData(int contractID)
    {
        List<Contract> returnValue = new List<Contract>();
        ... /*data retrieval logic*/
        while(reader.Read())
        {
            Contract contract = new Contract();
            contract.CustomerID = Convert.ToInt32(reader["CustomerID"]);
            contract.CustomerName = reader["CustomerName"].ToString();
            ...
            if(!returnValue.Contains(contract))
                returnValue.Add(contract);
        }
        reader.Close();
        command.Dispose();
        return returnValue();
    }
}
</code>

But I soon realized that this is bad because I had to check to see if this ContractID has any TermsID associated with it and the way it currently is I would have to do something like:

if(ContractDataMapper.GetContractData(1234)[0].TermsID > 0)
    // Do something

Ideally I should have one class Contract and have other properties in a subclass. Now my question is ... do you think it would be better to have a struct or a subclass or something else?

// Something like this
Contract contract = new Contract(1234);
List<SubsetData> subset = contract.SubsetData;

I would appreciate your help.

Re: Design Question (Class vs Structs)

PIEBALDconsult1-Sep-09 8:54

PIEBALDconsult

1-Sep-09 8:54

Probably a class.

using webbrowser to Interact with a Flash control???

Member 65252411-Sep-09 6:54

Member 6525241

1-Sep-09 6:54

using Automation (SHDocVw, MSHTML or something else?) or a WebBrowser control:
1)Is it possible to interrogate a flash control to discover its elements? For example, http://demo.garanti.com.tr/bireysel_demo/main.html[^], there are flash buttons. Can I determine there "ID"s?
2)Given the "ID" names of elements in a flash control, is it possible to click and/or select them?

Database connection question

tonyrdye1-Sep-09 6:35

tonyrdye

1-Sep-09 6:35

New to C# - long time cobol programmer....

How do you define a db connection so it can be used across several windows forms?
I have the connection working but I have to establish the connection in each form.

iDB2Connection cn = new iDB2Connection();
cn.ConnectionString = "DataSource=" + txtiSeries.Text.Trim(' ')
+ ";DefaultCollection=" + txtDataLibrary.Text.Trim(' ')
+ "; UserID=" + txtUserId.Text.Trim(' ')
+ "; Password=" + txtPwd.Text.Trim(' ') + ";LibraryList=*USRLIBL;";
try
{
cn.Open();
}
catch (iDB2CommErrorException x)

I would like to be able to establish the connection 1 time when the application starts and then be able to use it
across all of the windows forms.

Just not sure were or how to define it.

Any help would be appreciated.

Thanks

musefan1-Sep-09 6:43

musefan

1-Sep-09 6:43

It would be a bad idea to keep the database connection open constantly, It is much better to create a connection each time you need one.

I tend to use a class that does all my database work, which includes creating a connection when needed. This class provides functions for specifying search criteria. You could consider a simple class that simply takes an SQL query string and returns a datatable of the results (for search functionality) - In this case database connection string could be a static member of the class which is set when the application first loads.

Life goes very fast. Tomorrow, today is already yesterday.

Kevin Marois1-Sep-09 18:24

Kevin Marois

1-Sep-09 18:24

Create a data class that handles all data calls to & from the data source. I have one if you need it.

Then in your main class, mine is called csApp, create a class variable that holds it:

public static DataClass DataAccess;

Next, in the Main method do:

public static void Main(String[] args)
{
    DataAccess = new DataClass();
}

Then, anytime you need to call into the data source you can do:

DataSet ds = csApp.DataAccess.GetDataSet("select * from ....")

This way it's always available. And you should always close the connection when you're
not using it.

Everything makes sense in someone's mind

seoamitk1-Sep-09 22:42

seoamitk

1-Sep-09 22:42

Hi
You can an app.config file to your project and write this code into it

<configuration>
<appsettings>
<add key="Accesskey" value="Data source=;Initial catalog=;user id=;Password=">

if you have done this write this code your destination form where you have to make connection.

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
using System.Data.SqlClient;

namespace WindowsApplication9
{
public partial class Form1 : Form
{
SqlConnection connection;
string con;
public Form1()
{
con = System.Configuration.ConfigurationSettings.AppSettings["Accesskey"].ToString();
connection = new SqlConnection(con);
InitializeComponent();
}

private void Form1_Load(object sender, EventArgs e)
{
connection.Open();
}
}
}

Here this code writern in C# language you have to just convert it into VB.NET.

Getting DBMS/Database server list using C#

seoamitk1-Sep-09 23:06

seoamitk

1-Sep-09 23:06

hi

?xml version="1.0" encoding="utf-8" ?
<configuration>
<appSettings>
<add key="Accesskey" value="Data source=.;Initial catalog=kirti;user id=sa;Password=./>
</appSettings>
</configuration>

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
using System.Data.SqlClient;

namespace WindowsApplication9
{
public partial class Form1 : Form
{
SqlConnection connection;
string con;
public Form1()
{
con = System.Configuration.ConfigurationSettings.AppSettings["Accesskey"].ToString();
connection = new SqlConnection(con);
InitializeComponent();
}

private void Form1_Load(object sender, EventArgs e)
{

}

private void button1_Click(object sender, EventArgs e)
{
try
{
connection.Open();
SqlCommand commad = new SqlCommand("select *from " + textBox1.Text.ToString() + "", connection);
SqlDataAdapter ad = new SqlDataAdapter(commad);
DataSet ds = new DataSet();
ad.Fill(ds);
dataGridView1.DataSource = ds.Tables[0];

}
catch (Exception ex)
{
MessageBox.Show(ex.Message.ToString());
}
finally
{
connection.Close();
}
}
}
}

This code is writren in C# you have just convert into VB.NET.

AhmedMasum1-Sep-09 3:59

AhmedMasum

1-Sep-09 3:59

Hi all,
Can some one tell me how can I get a list of different DBMS/ Database server, those are installed in a computer using C#.

Henry Minute1-Sep-09 4:17

Henry Minute

1-Sep-09 4:17

For SqlServer only:

private void GetServerList()
{
    DataTable dt;

    // Set local server as default
    dt = SmoApplication.EnumAvailableSqlServers(false);
    if (dt.Rows.Count > 0)
    {
        // Load server names into combo box
        foreach (DataRow dr in dt.Rows)
        {
            ServerNamesComboBox.Items.Add(dr["Name"]);
        }

        // Default to this machine
        ServerNamesComboBox.SelectedIndex
            = ServerNamesComboBox.FindStringExact(
            System.Environment.MachineName);

        // If this machine is not a SQL server
        // then select the first server in the list
        if (ServerNamesComboBox.SelectedIndex < 0)
        {
            ServerNamesComboBox.SelectedIndex = 0;
        }
    }
    else
    {
        ExceptionMessageBox emb = new ExceptionMessageBox();
        emb.Text = Properties.Resources.NoSqlServers;
        emb.Show(this);
    }
}

cannot help with non-SqlServer DBMSs.

Henry Minute

Do not read medical books! You could die of a misprint. - Mark Twain
Girl: (staring) "Why do you need an icy cucumber?"
“I want to report a fraud. The government is lying to us all.”

AhmedMasum1-Sep-09 4:28

AhmedMasum

1-Sep-09 4:28

Thanks for reply.
But I can not run this because of the following errors:

Error 2 The name 'SmoApplication' does not exist in the current context

Error 3 The type or namespace name 'ExceptionMessageBox' could not be found (are you missing a using directive or an assembly reference?)

Error 4 The type or namespace name 'ExceptionMessageBox' could not be found (are you missing a using directive or an assembly reference?)

Error 5 'WindowsApplication1.Properties.Resources' does not contain a definition for 'NoSqlServers'

Henry Minute1-Sep-09 4:38

Henry Minute

1-Sep-09 4:38

All of the code can be run using standard .NET Framework references.

Google, or search MSDN, for smoapplication. From there you will find links to information that will help you to get it running.

As part of the process you will have to add references to the following assemblies:

// SMO namespaces
using Microsoft.SqlServer.Management.Common;
using Microsoft.SqlServer.Management.Smo;
using Microsoft.SqlServer;
using Microsoft.SqlServer.MessageBox;

The code comes from one of the SqlServer samples downloads, from MSDN.