C# | Get an enumerator that iterates through the Hashtable

Hashtable.GetEnumerator Method is used to returns an IDictionaryEnumerator that iterates through the Hashtable. Syntax:

public virtual System.Collections.IDictionaryEnumerator GetEnumerator ();

Return Value: It returns an IDictionaryEnumerator for the Hashtable. Below programs illustrate the use of Hashtable.GetEnumerator Method: Example 1: Output:

B --> Banana
C --> Cat
A --> Apple
F --> Fish
D --> Dog
E --> Elephant

Example 2:

Output:

III --> third
IV --> fourth
V --> fifth
II --> second
I --> first

Note:

• The foreach statement of the C# language hides the complexity of the enumerators. Therefore, using foreach is recommended, instead of directly manipulating the enumerator.
• Enumerators can be used to read the data in the collection, but they cannot be used to modify the underlying collection.
• Current returns the same object until either MoveNext or Reset is called. MoveNext sets Current to the next element.
• An enumerator remains valid as long as the collection remains unchanged. If changes are made to the collection, such as adding, modifying, or deleting elements, the enumerator is irrecoverably invalidated and its behavior is undefined.
• This method is an O(1) operation.

Reference:

• https://learn.microsoft.com/en-us/dotnet/api/system.collections.hashtable.getenumerator?view=netframework-4.7.2