HiveBrain v1.2.0
Get Started
← Back to all entries
snippetcsharpCritical

How do you get the index of the current iteration of a foreach loop?

Submitted by: @import:stackoverflow-api··
0
Viewed 0 times
indexyouhowiterationthecurrentloopforeachget

Problem

Is there some rare language construct I haven't encountered (like the few I've learned recently, some on Stack Overflow) in C# to get a value representing the current iteration of a foreach loop?

For instance, I currently do something like this depending on the circumstances:

int i = 0;
foreach (Object o in collection)
{
    // ...
    i++;
}

Solution

The foreach is for iterating over collections that implement IEnumerable. It does this by calling GetEnumerator on the collection, which will return an Enumerator.

This Enumerator has a method and a property:

  • MoveNext()



  • Current



Current returns the object that Enumerator is currently on, MoveNext updates Current to the next object.

The concept of an index is foreign to the concept of enumeration, and cannot be done.

Because of that, most collections are able to be traversed using an indexer and the for loop construct.

I greatly prefer using a for loop in this situation compared to tracking the index with a local variable.

Context

Stack Overflow Q#43021, score: 676

Revisions (0)

No revisions yet.