The Hashtable class represents a collection of key-and-value pairs that are organized based on the hash code of the key. The key is used to access the items in the collection. Hashtable.Add(Object, Object) Method is used to adds an element with the specified key and value into the Hashtable.
public virtual void Add(object key, object value);
key: It is the specified key of the element to add of type System.Object.
value: It is the specified value of the element to add of type System.Object. The value can be null.
- ArgumentNullException : If the key is null.
- ArgumentException : If an element with the same key already exists in the Hashtable.
- NotSupportedException : Either Hashtable is read-only or Hashtable has a fixed size.
Below given are some examples to understand the implementation in a better way :
Example 1 :
d: data structures c: c++ q: quiz g: geeks
5: Odd and Prime 9: Odd 2: Even and Prime 4: Even
- C# | Remove the element with the specified key from the Hashtable
- C# | Check if a Hashtable is equal to another Hashtable
- C# | Adding an element to the List
- C# | Get or Set the value associated with specified key in Hashtable
- C# | Hashtable Class
- C# Hashtable with Examples
- C# | Check whether a Hashtable contains a specific key or not
- C# | Check if Hashtable is read-only
- C# | Check if the Hashtable contains a specific Key
- C# | Get an enumerator that iterates through the Hashtable
- C# | How to get hash code for the specified key of a Hashtable
- C# | Gets an ICollection containing the keys in the Hashtable
- Difference between Hashtable and Dictionary in C#
- C# | Gets an ICollection containing the values in the Hashtable
- C# | Remove all elements from the Hashtable
- C# | Check if the Hashtable contains a specific Value
- C# | Count the number of key/value pairs in the Hashtable
- C# | Check if Hashtable has a fixed size
- How to create a shallow copy of Hashtable in C#
- C# | Copying the Hashtable elements to an Array Instance
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