Can dictionary have two keys?
No, each key in a dictionary should be unique. You can’t have two keys with the same value. If a key needs to store multiple values, then the value associated with the key should be a list or another dictionary.
Can a dictionary have multiple keys C#?
It’s a dictionary of dictionaries, so you have 2 keys to access each object, the key for the main dictionary to get you the required sub dictionary, and then the second key for the sub dictionary to get you the required item.
Can we use tuple as key in dictionary c#?
just make a simple key class derived from a tuple. So you can use it with dictionary: var myDictinaryData = new Dictionary() { {new myKey(1, 2, 3), “data123”}, {new myKey(4, 5, 6), “data456”}, {new myKey(7, 8, 9), “data789”} };
Can dictionary have 2 Keys Python?
A dictionary in Python is a mutable, unordered collection of key-value pairs. Creating a dictionary with multiple keys mapped a single value allows a user to modify the value at all keys that share that value at the same time.
Are dictionary keys mutable?
Values can be any type of object, but keys must be immutable. Dictionaries themselves are mutable, so entries can be added, removed, and changed at any time. Note, though, that because entries are accessed by their key, we can’t have two entries with the same key.
What is Ilookup?
It’s a cross between an IGrouping and a dictionary. It lets you group items together by a key, but then access them via that key in an efficient manner (rather than just iterating over them all, which is what GroupBy lets you do). For example, you could take a load of .NET types and build a lookup by namespace…
Can a dictionary key be an object c#?
The C# “Dictionary” class is a generic type. The keys in a dictionary can be a reference type, i.e., objects.
Which is faster dictionary or tuple C#?
The Tuple method is similar to the above snippets, and while it is faster than the Dictionary, KeyValuePair> , it is still nowhere near as fast as indexing directly into the collection to the desired value based on a hashed key, as is done in the MultiKeyDictionary class.
What is tuple C#?
The Tuple class was introduced in . NET Framework 4.0. A tuple is a data structure that contains a sequence of elements of different data types. It can be used where you want to have a data structure to hold an object with properties, but you don’t want to create a separate type for it.
Is C# Dictionary A Hashtable?
The Dictionary class is a type-safe Hashtable implementation, and the keys and values are strongly typed. When creating a Dictionary instance, you must specify the data types for both the key and value. Dictionary is NOT implemented as a HashTable, but it is implemented following the concept of a hash table.
