In-depth foreach work

The ienumerable interface is responsible for using the foreach loop.

The following describes how to iterate a collection of collectionobject in foreach as follows:

1. Call collectionobject. getenumerator () and return an ienumerator reference. This method can be implemented through the ienumerable interface.CodeBut this is optional.

2. Call the movenext () method of the returned ienumerator interface.

3. If the movenext () method returns true, use the current attribute of the ienumerator interface to obtain a reference of the object for foreach loop.

4. Repeat the previous two steps until the movenext () method returns false, and the loop stops.