interface

[smileyface5]

im not sure what "interface does". ive tried finding help in tutorials but cant find anything that explains what it does.

could anyone explain what this code does?

public interface IAnimal {

int Legs { get; set; }

string Walk();
}

public class Dog : IAnimal {

public int Legs {
get {
return 4;
}
set {
}
}

public string Walk() {
return "I want to run";
}
}

[nemaroller]

An interface is a cookie-cutter template of sorts.

It declares methods, properties, but cannot define them.

Interfaces are useful when an application must be created to communicate with other parts of a larger multi-tier or component-model application. They also help enforce code integrity - any class that derives from an interface that does not implement the required functionality will fail at compile time - which immediately alerts the developer that something is missing.

In the code, you posted, if you remove the public string Walk(){} function from the Dog class, and try to compile, the compiler will immediately let you know you have a problem. This is especially useful in large enterprise applications. Obviously, for a single developer, you KNOW are building the whole thing, so you know what needs to be passed to a class, what logic needs to be done and vice versa.

Reading the above paragraph, I assure you will not help - I'm not very articulate on some things. A simple search on 'C# Interfaces tutorial' in google should give you all the help you need.

[Magiaus]

The biggest thing an interface does is states that your class abides by the contract stated in IWhatever.

public interface IHaveControls
{
    ControlCollection Ctl{get;set;}
}

public class Widget : IHaveControls
{
   ....Implement
}

void foo(object o)
{
     if(o is IHaveControls)
     {
           IHaveControls iCtl = o As IHaveControls;
           foreach(Control ctl in iCtl.Ctl)
           {
                 ctl.BgColor = Color.Black;
           }
     }
}