Dictionary<TKey,TValue>.Add() Method is used to add a specified key and value to the dictionary.
public void Add (TKey key, TValue value);
key: It is the key of the element to add.
value: It is the value of the element to add. The value can be null for reference types.
- ArgumentNullException : If the key is null.
- ArgumentException : If an element with the same key already exists in the Dictionary.
Below are the programs to illustrate the use of Dictionary<TKey,TValue>.Add() Method:
Total key/value pairs in myDict are : 6 The key/value pairs in myDict are : Key = Australia, Value = Canberra Key = Belgium, Value = Brussels Key = Netherlands, Value = Amsterdam Key = China, Value = Beijing Key = Russia, Value = Moscow Key = India, Value = New Delhi
An element with Key = "Russia" already exists.
- A key cannot be null, but a value can be if TValue is a reference type.
- If Count is less than the capacity, this method approaches an O(1) operation.
- If the capacity must be increased to accommodate the new element, this method becomes an O(n) operation, where n is Count.
- C# | Clone() Method
- C# | Replace() Method
- C# | StartsWith() Method
- C# | Insert() Method
- Queue.Contains() Method in C#
- C# | ToCharArray() Method
- C# | IsNullOrWhiteSpace() Method
- C# | Remove() Method
- C# | Copy() Method
- C# | ToUpper() Method
- Stack.Pop() Method in C#
- C# | ToLower() Method
- C# | PadRight() Method
- Decimal.Add() Method in C#
- Main Method in C#
If you like GeeksforGeeks and would like to contribute, you can also write an article using contribute.geeksforgeeks.org or mail your article to email@example.com. See your article appearing on the GeeksforGeeks main page and help other Geeks.
Please Improve this article if you find anything incorrect by clicking on the "Improve Article" button below.