what are Indexers in c# Dotnet

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Indexers in c# Dotnet

Chetan Sanghani · Answer

Indexers in C# are special types of properties that allow objects of a class or struct to be indexed just like arrays. They enable instances of a class to be accessed using the array-access syntax ( object[index] ), making your objects feel more intuitive and collection-like. public class SampleCollection { private T[] arr = new T[100]; public T this[int index] { get { return arr[index]; } set { arr[index] = value; } } } Key Points: Indexers are declared using the this keyword followed by a parameter list. They can be overloaded (i.e., multiple indexers with different parameter types). They can have any access modifier ( public , private , etc.). Indexers can be read-only , write-only , or read-write , just like properties. They do not have a name – they are always named this . var collection = new SampleCollection (); collection[0] = "Hello"; Console.WriteLine(collection[0]); // Output: Hello When to Use Indexers Use indexers when: Your class represents a collection or logical grouping of data. You want to simplify access to elements inside your class using intuitive syntax. Real-world Example public class DayCollection { private string[] days = { "Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday" }; public string this[int index] { get { if (index = days.Length) throw new IndexOutOfRangeException("Invalid index"); return days[index]; } } } // Usage DayCollection week = new DayCollection(); Console.WriteLine(week[1]); // Output: Monday Conclusion Indexers are a powerful feature in C# that help make your classes more flexible and user-friendly, especially when dealing with internal collections or mappings. By providing array-like access to class data, they improve code readability and usability.

Kiran Kumar · Answer

Thanks I am implementing app apart from storing days any specific logic I can use this feature like storing connection string

what are Indexers in c# Dotnet

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