For And For Each Loop In c#.net

Simple: A foreach loop works on each object in a collection, and provides that object as the appropriate type within the loop:

List<string> list = new List<string>() {"hello", "world"};
foreach (string s in list)
   {
   Console.WriteLine(s);
   }
// s is not available here.

This is really useful when you have to iterate though each element in a collection, but don't care what index they are at. In contrast, a for loop is more powerful, but harder to read and needs more care. To do the same thing with a for loop would be:

List<string> list = new List<string>() { "hello", "world" };
for (int index = 0; index < list.Count; index++)
    {
    string s = list[index];                
    Console.WriteLine(s);
    }

Generally, if you can use a foreach, you should - but you also have to remember that you cannot alter the collection in any way inside a foreach. If you try, you will get a runtime error. You can alter the collection (adding or removing items for example) within the for loop without any problems.

[edit]Tidied up indentation - OriginalGriff[/edit]

for Loop: for loop execute the statement or block of statement until the condition is false where it's containing with the length for statement repetition. for loop have three expression.

syntax of for loop: for(Value initialization;condition;increment/decrements)

ex: for(int i=0;i<=5;i++)
{
Console.WriteLine(i);
}



Fooreach loop: In foreeach loop do not need to specify the loop bound value as like minimum or maximum value. Execute a statement for each element of array or group of object.

systex of fooreach loop: foreach(variable declaration in group of object/array name)

ex:
int a = 0;

int[] no = new int[] { 0, 1, 2, 3, 4 };

foreach (int i in no )

{

a = a + i ;

}

foreach loops through all items in an array (for example)

a for loop has a exact count (like 20 loops)

int[] iarray = {1,2,3,4,5,6,7,8,9,10};

foreach(var item in iarray)
{
 Console.WriteLine(item.ToString());
}

//will give out
1
2
3
4
....
10

int[] iarray = {1,2,3,4,5,6,7,8,9,10};
for(int i = 0; i <=3;i++)
{
 Console.WriteLine(iarray[i].ToString());
}

//will give out
1
2
3
4