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Re: C# class constructor best practice ?

PIEBALDconsult4-Apr-15 8:27

PIEBALDconsult

4-Apr-15 8:27

BillWoodruff wrote:
it's a key part of the class' functionality to provide the lists

That sounds suspicious.

BillWoodruff wrote:
you to define a prototype for the Delegate Type

Yes, because I'm old-school, I try not to use new crap when the old crap still works just fine. I just didn't show it.

modified 4-Apr-15 14:36pm.

Re: C# class constructor best practice ?

Eddy Vluggen4-Apr-15 6:47

Eddy Vluggen

4-Apr-15 6:47

If you have a List of Actions to perform, then why are we talking about constructors? Why are you passing in an action, if you can pass an interface?

I'd also like to point out a recent thread[^] on the readability of the constructor Smile | :)

Bastard Programmer from Hell Suspicious | :suss:

If you can't read my code, try converting it here[^]

Re: C# class constructor best practice ?

BillWoodruff4-Apr-15 8:28

BillWoodruff

4-Apr-15 8:28

Hi,

I did, indeed, read the thread you refer to in the Lounge, with interest. In fact, my choice to implement multiple constructors ... what I consider best practice now ... one for each case ... is based on believing that improves code maintainability, and readability.

But, I did start this thread with the thought I might learn something new, and I'm certainly willing to change my current preferences Smile | :)

As I just posted to Piebald on this thread: "For the sake of focusing on what I think is the key issue ... handling the need to have a constructor with a variable number of parameters some of which may be Action or Func ... which are used dynamically in the ctor ... the code I showed here [in the original post on this thread] is deliberately as terse and simple as possible."

I can't grok what you are referring to when you say: "pass an interface;" and, I'm curious, how would that work ?

thanks, Bill

«To kill an error's as good a service, sometimes better than, establishing new truth or fact.» Charles Darwin in "Prospero's Precepts"

modified 4-Apr-15 15:09pm.

Re: C# class constructor best practice ?

PIEBALDconsult4-Apr-15 8:50

PIEBALDconsult

4-Apr-15 8:50

BillWoodruff wrote:
believing that improves code maintainability, and readability.

I'm with you on that. Thumbs Up | :thumbsup:

Re: C# class constructor best practice ?

Eddy Vluggen4-Apr-15 11:13

Eddy Vluggen

4-Apr-15 11:13

BillWoodruff wrote:
I can't grok what you are referring to when you say: "pass an interface;" and,
I'm curious, how would that work ?

You can't bind an interface to an action obvious. But if you can pass an Action<T> or Func<T>, then you can pass an object that implements a specific interface. It may require a bit more code, but the advantage of passing merely an interface appears obvious.

Bastard Programmer from Hell Suspicious | :suss:

If you can't read my code, try converting it here[^]

Re: C# class constructor best practice ?

BillWoodruff4-Apr-15 21:42

BillWoodruff

4-Apr-15 21:42

Hi, Eddy,

I believe I see the point you are making, and I certainly agree with you that passing an instance of #Whatever as an IWhatever is a good way to minimize what "parts" of an instance you expose. I can, and do, use interfaces that spec Funcs; example:

public interface IGenericWhatever<T> where T : struct
{
    Func<T, T> SomeFunc1 { set; get; }
    Func<T, T, T, List<T>> SomeFunc2 { set; get; }
}

For the particular "library for programmers" use case I am developing now, I find it appropriate for the programmer to pass Func definitions in the call to the Class' ctor.

When (if) I publish this library on CP, I'll ask for your review.

thanks, Bill

«To kill an error's as good a service, sometimes better than, establishing new truth or fact.» Charles Darwin in "Prospero's Precepts"

Re: C# class constructor best practice ?

Eddy Vluggen5-Apr-15 13:13

Eddy Vluggen

5-Apr-15 13:13

BillWoodruff wrote:
When (if) I publish this library on CP, I'll ask for your review.

Looking forward to the article Smile | :)

Bastard Programmer from Hell Suspicious | :suss:

If you can't read my code, try converting it here[^]

Is there any solution to design report instead of Crystal?

aahamdan4-Apr-15 4:14

aahamdan

4-Apr-15 4:14

Dear Expert,

Is there any solution or Programming method to develop reports without using Crystal reports in C#.

Ahmad

Re: Is there any solution to design report instead of Crystal?

OriginalGriff4-Apr-15 4:44

OriginalGriff

4-Apr-15 4:44

Well...there's Microsoft Reports[^]

Bad command or file name. Bad, bad command! Sit! Stay! Staaaay...

Re: Is there any solution to design report instead of Crystal?

tecnova14-Apr-15 4:58

tecnova1

4-Apr-15 4:58

You can use SSRS SQL Server Reporting Services with Report Builder. Also I have used ActiveReports several years back and would say it was once of the best experience. At the time I was working on a project replacing Crystal Reports with it.

Re: Is there any solution to design report instead of Crystal?

aahamdan4-Apr-15 10:14

aahamdan

4-Apr-15 10:14

I wonder if I can use some classes to develop reports, I need a dynamic report, that user can request same report in multiple design.

Re: Is there any solution to design report instead of Crystal?

tecnova18-Apr-15 14:54

tecnova1

8-Apr-15 14:54

Active Reports would be my recommendation. But I would suggest that you download a free copy and test it before you buy the full version.

http://activereports.grapecity.com[^]

Re: Is there any solution to design report instead of Crystal?

Eddy Vluggen4-Apr-15 6:50

Eddy Vluggen

4-Apr-15 6:50

Have you considered MS-Access?

Rich reporting and a free runtime Smile | :)

Bastard Programmer from Hell Suspicious | :suss:

If you can't read my code, try converting it here[^]

Re: Is there any solution to design report instead of Crystal?

Mycroft Holmes5-Apr-15 14:35

Mycroft Holmes

5-Apr-15 14:35

Choke cough spit you are really living up to your sig. Imagine inflicting Access on the poor bastard as a reporting tool, what a nightmare. Not as bad as CR but still has to be one of the lousiest choices.

Never underestimate the power of human stupidity
RAH

Re: Is there any solution to design report instead of Crystal?

Eddy Vluggen6-Apr-15 0:33

Eddy Vluggen

6-Apr-15 0:33

Mycroft Holmes wrote:
Imagine inflicting Access on the poor bastard as a reporting tool, what a nightmare

Howso?

I've used it without much problems Smile | :)

Bastard Programmer from Hell Suspicious | :suss:

If you can't read my code, try converting it here[^]

Best way to Sync data

Jassim Rahma3-Apr-15 11:55

Jassim Rahma

3-Apr-15 11:55

Hi,

I have a WinForm C# application with MySQL backend on the server in the company. The application needs to sync with a database on Web.

I thought of adding a is_synced field for the fields needs to be updated but then how can I sync? do I need to SELECT using the first mysql_local_connection and loop through avalable records then connect within the loop to mysql_cloud_connection and do the INSERT?

--> connect to mysql_local_connection
--> SELECT records need to be synced

--> While looping
--------> connect to mysql_cloud_connection
--------> INSERT or UPDATE
--> end loop

is this the best way to do it?

Thanks,
Jassim

Technology News @ www.JassimRahma.com

Re: Best way to Sync data

Afzaal Ahmad Zeeshan3-Apr-15 16:13

Afzaal Ahmad Zeeshan

3-Apr-15 16:13

If you want the best way to do this, then make sure your data is bound (Use binding[^]) and the Mode for binding is set to TwoWay, also that you're application is capturing every key stroke event and is updating the source by the target data (input). And once user has finished the work, commit the changes back to the database (this would ensure less latency delays).

Then you will be able to ensure (hopefully) that the data is synchronized among your Win Forms application and you MySQL database.

If you do not use data binding, then chances are that you're going handle events, create another background object to hold the data, then inside that class use other interfaces to commit data changes to database and so on. So, better is to use bindings.

The sh*t I complain about
It's like there ain't a cloud in the sky and it's raining out - Eminem
~! Firewall !~

comparing the columns of two tables

Member 107105323-Apr-15 2:49

Member 10710532

3-Apr-15 2:49

I'm sorry if I'm wrong section...
I'm doing an application in C#. I have two tables "Audience" and "Schedule" in the database. These tables have the column "Number", which store different values. I need to select from the first table "Audience" in the column "Number" all the values that are not found in the column "Number" table "Schedule" and results displayed in dataGridView. Tell me please how to make a select? how to write a SQL query?

Re: comparing the columns of two tables

Peter Leow3-Apr-15 3:01

Peter Leow

3-Apr-15 3:01

Use NOT EXISTS in the WHERE clause of the SQL, e.g.

SQL

SELECT * FROM audience a
WHERE NOT EXISTS
(SELECT * FROM schedule s WHERE a.number = s.number)

Refer: https://technet.microsoft.com/en-us/library/ms184297%28v=sql.105%29.aspx[^]

Re: comparing the columns of two tables

Member 107105323-Apr-15 3:22

Member 10710532

3-Apr-15 3:22

thank you so much! Smile | :)

error ExecuteReader()

Member 107105323-Apr-15 1:03

Member 10710532

3-Apr-15 1:03

Can you please tell how to fix the error.The debugger gives an error in the string: "SqlDataReader dr = com.ExecuteReader();".
writes:"There is a designated team of Command open DataReader, which requires the prior close."
Help me please.

class DAL
    {
        string connectionString = @"Data Source=...";
        public ArrayList GetNumber()
        {
            ArrayList getNum = new ArrayList();
            SqlConnection con = new SqlConnection(connectionString);
            SqlCommand com = new SqlCommand("SELECT * FROM Graphik", con);
            con.Open();
            com.ExecuteReader();
            SqlDataReader dr = com.ExecuteReader();
            if (dr.HasRows)
            {
                foreach (DbDataRecord result in dr)
                    getNum.Add(result);
            }
            con.Close();
            return getNum;
        }
    }