foreach - IEnumerable vs Property

[J. Marcelo Barbieri]

I managed to do a foreach to go through all the elements in class2 using a
public property, as you can find bellow.

I know I could obtain the same result implementing the IEnumerable
interface, but what would be the difference???

thanks,



namespace IndexerTest

{

class Class1

{



static void Main(string[] args)

{

int len = 2;

Class2 c2 = new Class2(len);

c2[0] = "First String";

c2[1] = "Second String";

foreach(string s in c2)...



}

}

public class Class2

{

public Class2(){}

public Class2(int i)

{

sa = new string;

}

private string[] sa;

public string this[int i]

{

get{return sa;}

set{sa = value;}

}

public string[]saProperty

{ get{return string[]sa;} }

}

}

 

[Marcelo]

You use GetEnumerator (IEnumerator). Let's say:

(found in MSDN)

using System;

public class SamplesArray {

public static void Main() {

// Creates and initializes a new Array.
String[] myArr = new String[10];
myArr[0] = "The";
myArr[1] = "quick";
myArr[2] = "brown";
myArr[3] = "fox";
myArr[4] = "jumped";
myArr[5] = "over";
myArr[6] = "the";
myArr[7] = "lazy";
myArr[8] = "dog";

// Displays the values of the Array.
int i = 0;
System.Collections.IEnumerator myEnumerator = myArr.GetEnumerator();
Console.WriteLine( "The Array contains the following values:" );
while (( myEnumerator.MoveNext() ) && ( myEnumerator.Current !=
null ))
Console.WriteLine( "[{0}] {1}", i++, myEnumerator.Current );

}

}

 

[Karen Albrecht [MSFT]]

IEnumerable gives you the ability to determine how a collection is sorted.
IEnumerable implements the IEnumerator interface. This interface has the
public methods MoveNext and Reset. How you implement these functions is up
to you.

 

[Jay B. Harlow [MVP - Outlook]]

J. Marcelo Barbieri,

Use something like:

public class Class2 : System.Collections.IEnumerable
{
// extra stuff trimmed

private string[] sa;

// extra stuff trimmed

#region IEnumerable support

public System.Collections.IEnumerator GetEnumerator()
{
return sa.GetEnumerator();
}

#endregion

}

Then you can delete the public saProperty property.

Hope this helps
Jay