[C#] How to use This Array

[Jelte]

at first is maybe practical to say that i am dutch, and so my english could be a little bit bad. :P

Hello everybody,

today i started to write a contact management application. and I use C# with the combination of XML(system.Xml) to make it work. at this moment i have a little problem with a array. the problem is that i dont know how to use the array in my script;

this is the array:

string [] Contactinfo;
            Contactinfo = new string[5] {"Name", "Lastname", "City", "Postcode"};

As you can see i declared the 4 arrays and give all of them a special name, the 1st Name, 2nd Lastname ect ect.

but if i use this array like this(see code below). it turns out into a build error:

Error 1 Cannot implicitly convert type 'string' to 'int'

xmltextwriter.WriteElementString("naam", Contactinfo["Name"]);

this sounds strange to me because the array is a string and i didnt gave the array a value yet.(is it maybe possible, cause the array doesn't have a value yet so it returns in 0, so it's a int?)

Thank you for your attention.

Jelte.

PS: does somebody knows a good beginner tutorial of C# and XML?

[Magos]

The strings you specified are the values of the array ("Name", "Lastname", etc...). To index each element you use zero-based integers (0, 1, 2, etc...).

If you still want to index by a string you could use a dictionary, to map string -> string.

var ContactInfo = new System.Collections.Generic.Dictionary<string, string>();

ContactInfo["Name"] = "John";
ContactInfo["Lastname"] = "Smith";
//etc...

Depending on what you're trying to achieve it may be better to store the data in a struct or class:

class ContactInfo
{
  public string Name;
  public string Lastname;
  //etc...
}

var MyInfo = new ContactInfo();

MyInfo.Name = "John";
MyInfo.LastName = "Smith";

(in the above sample it's usually better to make a constructor that takes arguments, but that's another story)

[Jelte]

@Magos thanks for your reply, i knew that the original method of indexing is the zero-based, but i though i saw on some site that you can use: (see code below) to replace the numbers in this words.

Contactinfo = new string[5] {"Name", "Lastname", "City", "Postcode"};

And Thanks so add the Code-Snippets in your message but i'am not yet that skilled that i can handle classes(i hope i will come in the future):P

Greetings

J.

[indigo0086]

you really should learn about classes early on since everything you do involves them. You shouldn't be using a string[] to represent an entity or object. It has no behavior, no convenient state, nor a convenient interface for users. The basics of classes are simple, you should learn them.

[Jelte]

indigo0086: thanks for your reply, do you have some good suggestion for a good tutorial about classes?

Greetings Jelte.

[GanglyLamb]

@Jelte: Normally my initial reply to your last question would be: look it up on google. (this site has tutorials as well but not for C# since thats not the real focus here).

But since you also speak dutch which is something rare on this board (except for Maes who hasnt been on since ages ) I'll do the google for you:

First hit on google for C# class tutorial

In elk geval welkom!

[Jelte]

Thanks you all, for your Help