Re: A typical case about interfaces - C# Discussion Boards

5-Jun-07 20:35

the following code is in C#

I have 2 interfaces

public interface Interface1
{
string ReturnString1();
}
public interface Interface2
{
string ReturnString1();
}

now i implement both the interfaces in a single class

Class A:Interface1,Interface2
{
}

now according to my searchings i found that we can implement both the interfaces in the following manner

Class A:Interface1,Interface2
{
public string Interface1.ReturnString1()
{
return "Interface1.ReturnString1";
}
public string Interface2.ReturnString1()
{
return "Interface2.ReturnString1";
}
}

but on compiling it is giving an error:"the modifier public is not valid for this item"

after i remove public and then i compile the code, it compiles successfully
but i'm not able to access these methods by creating an object of the class.

Can anyone solve this problem

Amit More (CMC)

-- modified at 3:01 Wednesday 6th June, 2007

Amit More (CMC)

Christian Graus5-Jun-07 20:50

Christian Graus

5-Jun-07 20:50

amitcoder83 wrote:
string ReturnString1();

the default access for any method or property is private. If you remove 'public' then they default to private right through your code.

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 )

Manoj Kumar Rai5-Jun-07 21:01

5-Jun-07 21:01

I think you are not correct Smile | :)

Manoj
Never Gives up

originSH5-Jun-07 22:27

originSH

5-Jun-07 22:27

Manoj Kumar Rai wrote:
I think you are not correct

You could atleast provide an explination rather than going round insulting people.

If you explain why then people will be thankful of learning something new rather than thinking your an arse Wink | ;)

originSH5-Jun-07 22:30

originSH

5-Jun-07 22:30

The default access for a method is public ... "but" ... when explicitly implimenting an interface method it is automatically public and you cannot put any modifier on it, even the public one.

Explicit Interface Implementation Tutorial[^]

How to: Explicitly Implement Interface Members (C# Programming Guide)[^]

Manoj Kumar Rai5-Jun-07 21:00

Re: A typical case about interfaces [modified]

5-Jun-07 21:00

Its correct that modifier public is not valid for those function.

Also pls make sure you are accessing those function from a object type of Interface1 or Interface2 and not from a object of the class A directly, to get the access to those function.

i.e.

Interface1 interface1 = new A();

interface1.ReturnString1(); //Here you will be able to access the function.

Manoj
Never Gives up

amitcoder835-Jun-07 21:05

5-Jun-07 21:05

All the code is in C#,
so if i dont specify access modifier then by default it is public
after implementing the methods in an interface we can access the methods thru that class's object.why can't we do the same with this.

Amit More(CMC)

-- modified at 3:10 Wednesday 6th June, 2007

Manoj Kumar Rai5-Jun-07 21:10

5-Jun-07 21:10

See the function name in the class A is as Interface1.ReturnString1(), and thats why you can not a.ReturnString1(). But the function name for the Interface1 is "ReturnString1" and you can call it using object of type Interface1.

Manoj
Never Gives up

amitcoder835-Jun-07 21:16

5-Jun-07 21:16

can u give me a code snippet about how actually u implement it

Manoj Kumar Rai5-Jun-07 21:27

5-Jun-07 21:27

I wrote you code in the previous replies it self.

In your case:

A aa = new A();

//Cast it to interface
Interface1 interface1 = aa;

//Now u can call the Function ReturnString1

interface1.ReturnString1();

Also you can write it as:

((Interface1)aa).ReturnString1();

Manoj
Never Gives up

amitcoder835-Jun-07 21:32

5-Jun-07 21:32

thank u very much for ur proper consultation.

Please Help

codingrocks5-Jun-07 20:07

5-Jun-07 20:07

I am doing a project and completed some phases...

I am using Microsoft Visual Studio 2005 Version 8.0.50727.42 (RTM.050727-4200)and
Microsoft .NET Framework Version 2.0.50727

Microsoft Visual C# 2005 with MS SQL server 2000

I am getting a problem when i try to extract a data from rows or columns to a textbox...
the connectivity works well...

how can i do it...?

plz help.....

SAJAN A PILLAI
C#.NET Programmer
TELESOFT INDIA PVT LTD...
BANGALORE

Re: Please Help

Christian Graus5-Jun-07 20:14

Christian Graus

5-Jun-07 20:14

I recommend reading any of the guides commonly available online on how to ask questions.

1 - the information you provide about your version is superfluous, VS2005 would have been fine
2 - your header is meaingless, 'please help' says nothing about your problem
3 - how can we help you without seeing the code you've written ? WE have no idea how you are hoping to bind a textbox to a value, or how you know that connectivity works well, despite your issue.

[Message Deleted]

codingrocks5-Jun-07 20:25

Re: To bind a value from DataGridView to textbox

5-Jun-07 20:25

[Message Deleted]

Christian Graus5-Jun-07 20:43

Christian Graus

5-Jun-07 20:43

I don't know if there's an automated way to do this, or if you need to write your own plumbing code to assign the values and then push them back into the DB as needed.

Re: To bind a value from DataGridView to textbox

Manoj Kumar Rai5-Jun-07 20:46

Re: To get a selected value from datagrid view

5-Jun-07 20:46

You can set the DataGridview enditable. In the Save button handler code get the edited data from the grid and updated into the database.

Manoj
Never Gives up

Manoj Kumar Rai5-Jun-07 21:06

Re: To get a selected value from datagrid view

5-Jun-07 21:06

something like below:

dataGridView1.SelectedRows[0].Cells[0].Value will give you the valuse of cell#1 from the 1st row selected.

Manoj
Never Gives up

codingrocks5-Jun-07 21:12

Re: To get a selected value from datagrid view

5-Jun-07 21:12

when i am assigning it to a textbox like

txtcuscode.Text= dataGridView1.SelectedRows[0].Cells[0].Value;

shows an error message like this following..

Cannot implicitly convert type 'object' to 'string'.

plz help me recover this and thanks a lot for the code.....

SAJAN A PILLAI

C#.NET Programmer
TELESOFT INDIA PVT LTD...
BANGALORE

Manoj Kumar Rai5-Jun-07 21:13

Cast done to string ..but error comes

5-Jun-07 21:13

cast "dataGridView1.SelectedRows[0].Cells[0].Value" to a string.

Manoj
Never Gives up

codingrocks5-Jun-07 21:20

Re: Cast done to string ..but error comes

5-Jun-07 21:20

casting done to string...

but error appears...like

Index was out of range. Must be non-negative and less than the size of the collection. Parameter name: index

the error is at this line...

txtcuscode.Text= Convert.ToString(dataGridView1.SelectedRows[0].Cells[0].Value);

the error handler points to the property text of the textbox...

help me overcome this..

SAJAN A PILLAI

C#.NET Programmer
TELESOFT INDIA PVT LTD...
BANGALORE

codingrocks5-Jun-07 22:19