C# Discussion Boards - CodeProject

6-Jan-09 18:12

dear friends pls help me in this

wats the equalent operator for

1.this pointer ->

2. scope resolution operator ::

3. pointers

4.arrays

5. matrix

6.memory allocation and free up

pls explain with example codes

«_Superman_»6-Jan-09 18:55

«_Superman_»

6-Jan-09 18:55

this-> becomes this.

:: becomes .

pointers can be used with the unsafe keyword and is still *, but not recommended as garbage collection will be effected

arrays are the same [] but is written as string[] s = new string[3];

by matrix if you mean 2 dimensional arrays then they are declared as string[,]
there is also something called jagged arrays - string[][]

memory allocation is using new
free up happens through the garbage collector (automatic)

«_Superman_»

lawrenceinba6-Jan-09 20:28

6-Jan-09 20:28

thanks friend

Guffa6-Jan-09 19:02

Guffa

6-Jan-09 19:02

lawrenceinba wrote:
1.this pointer ->

->

(Pointers can only be used in an unsafe context.)

lawrenceinba wrote:
2. scope resolution operator ::

base.

lawrenceinba wrote:
3. pointers

References (or in some cases pointers).

lawrenceinba wrote:
4.arrays

Array objects.

lawrenceinba wrote:
5. matrix

Do you mean a two dimensional array or matrix mathematics?

lawrenceinba wrote:
6.memory allocation and free up

Create and release objects.

Despite everything, the person most likely to be fooling you next is yourself.

lawrenceinba6-Jan-09 20:27

6-Jan-09 20:27

thanks friend.. its very useful for me

ya two dimensional matrix

book

Luc Pattyn6-Jan-09 23:24

Luc Pattyn

6-Jan-09 23:24

Hi,

if you need to understand or create C# programs, I strongly suggest you buy an introductory book on the language and work your way through it; that may take a day or two, but will provide you much more knowledge and insight than one hundred questions and answers can provide.

Smile | :)

Luc Pattyn [Forum Guidelines] [My Articles]

Love, happiness and fewer bugs for 2009!

Re: book

lawrenceinba6-Jan-09 23:45

6-Jan-09 23:45

k friend

C# - Static classes

DineshSharmain6-Jan-09 18:08

DineshSharmain

6-Jan-09 18:08

Hi All,
I am really confused with.....static classes...its harmful or beneficial in terms of scalability.

no. of users are accessing one static method of static class.....that performs any operation like data insertion, update, deletion and fetching from database.....

my confusion is that...while all users will be calling the same method using class directly then it will maintain the version or all users will be in Q.
or something else.... I am eager to know .....

Thanks

Dinesh Sharma

Guffa6-Jan-09 18:45

Guffa

6-Jan-09 18:45

I don't really understand your question, but I'll try to shed some light.

If you are building a multi-threaded application (like an ASP.NET web application), then each thread needs to have it's own connection object when working with the database. If you are trying to use the same connections for all threads, only one thread at a time can access the database, and that would indeed be harmful for the scalability.

Despite everything, the person most likely to be fooling you next is yourself.

«_Superman_»6-Jan-09 19:00

«_Superman_»

6-Jan-09 19:00

static classes can only contain static members.
These classes cannot be instantiated using new and are automatically loaded by the runtime.

If the static methods refers to static variables they are not thread safe.

«_Superman_»

N a v a n e e t h6-Jan-09 19:08

6-Jan-09 19:08

DineshSharmain wrote:
no. of users are accessing one static method of static class.....that performs any operation like data insertion, update, deletion and fetching from database.....

There is no harm in using it when the static method is not using any shared variables. See the following code

public static class Foo
{
   public static void FooMethod(string a,string b){
      ....
   }
}

In the above example, FooMethod is safe as it is not using any shared objects. Whenever you use FooMethod, you will have separate copy of variable a and b.

public static class Foo
{
   private static string FooVariable = "";
   public static void FooMethod(){
        // use FooVariable here
   }
}

Above given code is not safe as static variable(FooVariable) is shared across multiple threads. Read about thread synchronization techniques.

Navaneeth

How to use google | Ask smart questions

DineshSharmain6-Jan-09 19:50

DineshSharmain

6-Jan-09 19:50

Thanks for your reply.....
my problem is not related to database....its related to performance & scalability of static classes.

code is as follows -

static public class TempExample
{
static public bool GetCombo(object a, out DataSet dsAccountClass, string strClassType)
        {

            IDBHelper intfDBHelper = DBClient.GetDBHelper();
            dsAccountClass = new DataSet();
            IDataParameter[] arParms = intfDBHelper.CreateDBParamsArray(2);
            arParms[0] = intfDBHelper.CreateNewDBParam("ID", SqlDbType.NVarChar, 6);
            arParms[0].Value = a.strA;
            arParms[1] = intfDBHelper.CreateNewDBParam("ClasificationType", SqlDbType.NVarChar, 1);
            arParms[1].Value = strClassType;
            try
            {
                using (IDbConnection connection = DBClient.GetConnection(a.strSystem))
                {
                    intfDBHelper.FillDataset(connection, CommandType.StoredProcedure, "p_GetSpConditionCalssCombo", dsAccountClass, new string[] { "dt_ProductClassID" }, arParms);
                }

                if (dsAccountClass.Tables[0].Rows.Count == 0)
                    return false;
                return true;
            }
            catch (Exception ex)
            {
                throw DBClientUtils.GetDBErrorMessages(ex, a.strUser);
            }
            finally
            {
                dsAccountClass.Dispose();
            }

        }
}

Multiple user will be accessing this class without creating an object so what will happen if 100 users are trying to access the same method of class at the same time.

Dinesh Sharma

N a v a n e e t h6-Jan-09 20:06

Re: C# - Static classes [modified]

6-Jan-09 20:06

DineshSharmain wrote:
its related to performance & scalability of static classes.

Static classes will be invoked when any of the members are accessed for the first time and it will be available in memory until the application domain unloads.

DineshSharmain wrote:
if 100 users are trying to access the same method of class at the same time

Nothing will happen. I reiterate, if your method is using another static variables, then you need synchronization mechanisms to ensure one thread will modify it at a time. If it is not using any static variables, your method is safe.

Smile | :)

Navaneeth

How to use google | Ask smart questions

DineshSharmain6-Jan-09 20:42

DineshSharmain

6-Jan-09 20:42

Thanks Navneet
wat about the code....I have given....is this thread safe

may i get any deadlock situation in my application due to this ...as m getting if load increase on application so m digging all this.

Dinesh Sharma

modified on Wednesday, January 7, 2009 2:52 AM

N a v a n e e t h6-Jan-09 20:53

Re: Extract All text values

6-Jan-09 20:53

I don't know what is methods DBClient.GetDBHelper() and intfDBHelper.CreateDBParamsArray(2) doing and where dsAccountClass variable is declared. Other than that, I think it is safe.

Navaneeth

How to use google | Ask smart questions

Extract All text values

belzer6-Jan-09 15:51

belzer

6-Jan-09 15:51

Hello Forum

I need to translate an existing application to multiple langauages,

How can i extract all the text strings such as message box messages, text box values etc. so i know what i need to translate.

Please Help

Not Active6-Jan-09 15:54

Not Active

6-Jan-09 15:54

belzer wrote:
How can i extract all the text strings

Open the files and read

only two letters away from being an asset

Re: Extract All text values

N a v a n e e t h6-Jan-09 16:11