making this C# procedural function an OOP function - get rid of theparameters

[mesut]

hi colleagues,

I don't know if this is the right group for but it's in C# so I try.
I have a #3 procedural function called GetInfo.. and those are 3
overloaded methods. I would like to use the OOP approach to refactor
this.

The functions are working fine but I would like to have a OOP approach
can someone help me refactoring this??????

GeTInfo(System) -returns mutiple records - Dataset
GeTInfo(System, Key) -returns multiple records - Dataset
GeTInfo(System, Key,Value) -returns 1 record - Returns String
new approach:
- I created 3 properties
- I deleted the parms in the Functions it looks like GetInfo()

Function:
GetInfo()

3 Properties:
public String System{ get; set; }
public String Key{ get; set; }
public String Value{ get; set; }

Approach:
my aspx page should set the property, it can just the System or it can
be System, Key or it can be System, Key , Value. and then call the
GetInfo() function. The problem I have is: how can I decide how my
SQL should look like in WHERE clause. Because the previous procedural
I passed them as parameter and then used them in the WHERE. But I had
3 functions then (overloaded Methods)... Now I have 1 method... but
how can I decided how my SQL the Where clause should look like?

SELECT Name, Address, Zipcode FROM AddressBOOK where XXXXXXXXXXXXXX
is it with if (propertySystem != null) { //concat } If {propertyKey!=
null) {//concat}
etc etc.

can someone show the OOP approach?????? or the best practice...
thanks in advance,

mesut

[Tom P.]

My initial question is why not have the three overloaded methods?
GetInfo(System)
{
GetInfo(System, null, null);
}

GetInfo(System, Key)
{
GetInfo(System, Key, null);
}

GetInfo(System, Key, Info)
{
... do code things...
}
But, if you must continue on your current course then I'd build the
WHERE clause in the property accessor.

public string System
{
get{ }
set
{
_WhereClause += " and System = '" + value +"'";
}
}

or some such thing. Or build member strings that can be concatenated
into a WHERE clause when the GetInfo method is called.

Hope that helps,
Tom P.
On Jul 23, 12:05*pm, mesut <mesut.de...@no veonbe.comwrote :

hi colleagues,

I don't know if this is the right group for but it's in C# so I try.
I have a #3 procedural function called GetInfo.. and those are 3
overloaded methods. I would like to use the OOP approach to refactor
this.

The functions are working fine but I would like to have a OOP approach
can someone help me refactoring this??????

GeTInfo(System) -returns mutiple records *- Dataset
GeTInfo(System, Key) *-returns multiple records *- Dataset
GeTInfo(System, Key,Value) *-returns 1 record - Returns String

new approach:
- I created 3 properties
- I deleted the parms in the Functions it looks like GetInfo()

Function:
GetInfo()

3 Properties:
public String System{ get; set; }
public String Key{ get; set; }
public String Value{ get; set; }

Approach:
my aspx page should set the property, it can just the System or it can
be System, Key *or it can be System, Key , Value. *and then call the
GetInfo() function. The problem I have is: *how can I decide how my
SQL should look like in WHERE clause. Because the previous procedural
I passed them as parameter and then used them in the WHERE. But I had
3 functions then (overloaded Methods)... Now I have 1 method... but
how can I decided how my SQL the Where clause should look like?

SELECT Name, Address, Zipcode FROM AddressBOOK where XXXXXXXXXXXXXX

is it with if (propertySystem != null) { //concat *} *If {propertyKey!=
null) {//concat}
etc etc.

can someone show the OOP approach?????? or the best practice...

thanks in advance,

mesut

[Ben Voigt [C++ MVP]]

public string System

{
get{ }
set
{
_WhereClause += " and System = '" + value +"'";
}
}

or some such thing. Or build member strings that can be concatenated
into a WHERE clause when the GetInfo method is called.

Thinking your SQL belongs in the application (-10 points)
Building SQL by concatenation (-10 points)
Quoting input values instead of using parameterized queries (-100 points)
Exposing your users to SQL injection attack -- priceless

[Tom P.]

On Jul 23, 12:42*pm, "Ben Voigt [C++ MVP]" <[e-mail] spamwrote:

public string System
{
* * get{ }
* * set
* * {
* * * * _WhereClause += " and System = '" + value +"'";
* * }
}

or some such thing. Or build member strings that can be concatenated
into a WHERE clause when the GetInfo method is called.

Thinking your SQL belongs in the application (-10 points)
Building SQL by concatenation (-10 points)
Quoting input values instead of using parameterized queries (-100 points)
Exposing your users to SQL injection attack -- priceless

Fair enough, but he asked. I'm still trying to find out why function
overloading is not OOP.

Tom P.

[=?ISO-8859-1?Q?G=F6ran_Andersson?=]

mesut wrote:

hi colleagues,

I don't know if this is the right group for but it's in C# so I try.
I have a #3 procedural function called GetInfo.. and those are 3
overloaded methods. I would like to use the OOP approach to refactor
this.

The functions are working fine but I would like to have a OOP approach
can someone help me refactoring this??????

GeTInfo(System) -returns mutiple records - Dataset
GeTInfo(System, Key) -returns multiple records - Dataset
GeTInfo(System, Key,Value) -returns 1 record - Returns String

That is an OOP approach. Overloading is a part of polymorphism, which is
one of the main principles for OOP.

However, if what the methods do differ too much, you should give them
separate names instead. Also, it's somewhat impractical to have
overloads return different data types.

>
new approach:
- I created 3 properties
- I deleted the parms in the Functions it looks like GetInfo()

Function:
GetInfo()

3 Properties:
public String System{ get; set; }
public String Key{ get; set; }
public String Value{ get; set; }

Approach:
my aspx page should set the property, it can just the System or it can
be System, Key or it can be System, Key , Value. and then call the
GetInfo() function.

That's not a good approach at all. You have gone from an approach where
the method call is self describing, to an approach where it's not.

The problem I have is: how can I decide how my
SQL should look like in WHERE clause. Because the previous procedural
I passed them as parameter and then used them in the WHERE. But I had
3 functions then (overloaded Methods)... Now I have 1 method... but
how can I decided how my SQL the Where clause should look like?

SELECT Name, Address, Zipcode FROM AddressBOOK where XXXXXXXXXXXXXX
is it with if (propertySystem != null) { //concat } If {propertyKey!=
null) {//concat}
etc etc.

can someone show the OOP approach?????? or the best practice...
thanks in advance,

mesut

--
Göran Andersson
_____
http://www.guffa.com

[Ben Voigt [C++ MVP]]

That is an OOP approach. Overloading is a part of polymorphism, which

is one of the main principles for OOP.

???

Overridding is related to polymorphism, overloading is not.

[=?ISO-8859-1?Q?G=F6ran_Andersson?=]

Ben Voigt [C++ MVP] wrote:

>That is an OOP approach. Overloading is a part of polymorphism, which
is one of the main principles for OOP.

???

Overridding is related to polymorphism, overloading is not.

Everything that I read says that it is... For example:
"This type of polymorphism is sometimes known as overloading."

http://searchcio-midmarket.techtarge...212803,00.html
"Overloadin g is one type of polymorphism."

http://www.webopedia.com/TERM/O/overloading.html
"This type of polymorphism is common in object-oriented programming
languages, many of which allow operators to be overloaded in a manner
similar to functions (see operator overloading)."

http://en.wikipedia.org/wiki/Polymor...mputer_science)
"Overloadin g Polymorphism is the use of one method signature, or one
operator such as "+", to perform several different functions depending
on the implementation. "

http://en.wikipedia.org/wiki/Polymor...ed_programming
--
Göran Andersson
_____
http://www.guffa.com

[Alun Harford]

mesut wrote:

hi colleagues,

I don't know if this is the right group for but it's in C# so I try.
I have a #3 procedural function called GetInfo.. and those are 3
overloaded methods. I would like to use the OOP approach to refactor
this.

The functions are working fine but I would like to have a OOP approach
can someone help me refactoring this??????

GeTInfo(System) -returns mutiple records - Dataset
GeTInfo(System, Key) -returns multiple records - Dataset
GeTInfo(System, Key,Value) -returns 1 record - Returns String
new approach:
- I created 3 properties
- I deleted the parms in the Functions it looks like GetInfo()

Function:
GetInfo()

3 Properties:
public String System{ get; set; }
public String Key{ get; set; }
public String Value{ get; set; }

Approach:
my aspx page should set the property, it can just the System or it can
be System, Key or it can be System, Key , Value. and then call the
GetInfo() function. The problem I have is: how can I decide how my
SQL should look like in WHERE clause. Because the previous procedural
I passed them as parameter and then used them in the WHERE. But I had
3 functions then (overloaded Methods)... Now I have 1 method... but
how can I decided how my SQL the Where clause should look like?

SELECT Name, Address, Zipcode FROM AddressBOOK where XXXXXXXXXXXXXX

Oh dear. You've hit "the vietnam of computer science".

Good options are to either drop the idea of using OO here, to use an
automated ORM tool, or use an OODBMS.

Alun Harford

[=?ISO-8859-1?Q?Arne_Vajh=F8j?=]

Göran Andersson wrote:

Ben Voigt [C++ MVP] wrote:

>>That is an OOP approach. Overloading is a part of polymorphism, which
is one of the main principles for OOP.

???

Overridding is related to polymorphism, overloading is not.

Everything that I read says that it is... For example:

I think you read a bit selective then.

It should be obvious that it is possible to create
a procedural programming language that has function/subroutine
overloading.

"This type of polymorphism is common in object-oriented programming
languages, many of which allow operators to be overloaded in a manner
similar to functions (see operator overloading)."

http://en.wikipedia.org/wiki/Polymor...mputer_science)

This is under something it calls "Ad-hoc polymorphism". And
it says "Strachey [3] chose the term ad-hoc polymorphism to refer to..."
and the reference 3 is from 1967.

"Overloadin g Polymorphism is the use of one method signature, or one
operator such as "+", to perform several different functions depending
on the implementation. "

http://en.wikipedia.org/wiki/Polymor...ed_programming

I don't think this is talking about what you think it is.

I read it as if a sub class must have the methods and the
operators of the sub class. Which is polymorphism.

Arne

[mesut]

Hi colleagues,

thanks for sharing your thoughts with me.

First of all I think I should explain why I want to move to the
property way iso overloading methods.

I'm not strong in OOP but as far as I did my research (maybe not good
enough)... In OOP principles you work with objects.
and an objects has methods and properties as type.

the situation I have is :
my aspx page in presentation layer is calling the class object in the
Business logic layer. So those are separated.

My idea was if we work with objects then I should set the values in
propertie and then call the methods. Therefore I wished to delete the
parameters and use properties. the situation I have then is setting
the parameter then call the object. Since I've 3 methods doing
similair thing just the WHERE clause should be changed.

This is my statement, correct me if I'm wrong:
USE properties iso parameters in functions as much as I can, because
objects works with properties. A property has a get and set accessor
to check the value you pass. So I think using property is much more
OOP then passing parameters in functions... I guess.

let me give another example.

if you have a person class and method that returns address, city,
country of the that person.
The method is called GetPerson in thet Person class.

Which approach would you use....
1) call with parameter passing the peson ID: GetPerson(perso nID) -

>returning a dataset or a list ---- OR -----

2a) create a property in Person class and name it : PropertyPersonI D()
etc.
2b) set the property value and call this method: GetPerson()

ok.... which is more OOP... I think approach 2 is OOP. I guess...

Ok let's say I only know the person's first name and last name and I
would like to get all persons starting with these info. I would also
like name the method GetPerson. Because it's related to the person.

What I do is create 2 more properties in Person class name the
properties like 'propertyFirstN ame' and 'propertyLastNa me' then call
the GetPerson() method....

ok.... how would you handle this ? property approach??????

thanks
-mesut
ps: or would you just create 2 methods and overload them??????????? ???