set (C# Reference)

The set keyword defines an accessor method in a property or indexer that assigns a value to the property or the indexer element. For more information and examples, see Properties, Auto-Implemented Properties, and Indexers.

The following example defines both a get and a set accessor for a property named Seconds. It uses a private field named _seconds to back the property value.

class TimePeriod
{
     private double _seconds;

     public double Seconds
     {
         get { return _seconds; }
         set { _seconds = value; }
     }
}

Often, the set accessor consists of a single statement that assigns a value, as it did in the previous example. You can implement the set accessor as an expression-bodied member. The following example implements both the get and the set accessors as expression-bodied members.

class TimePeriod
{
    private double _seconds;

    public double Seconds
    {
        get => _seconds;
        set => _seconds = value;
    }
}

For simple cases in which a property's get and set accessors perform no other operation than setting or retrieving a value in a private backing field, you can take advantage of the C# compiler's support for auto-implemented properties. The following example implements Hours as an auto-implemented property.

class TimePeriod2
{
    public double Hours { get; set; }
}

C# language specification

For more information, see the C# Language Specification. The language specification is the definitive source for C# syntax and usage.

See also

• C# Keywords
• Properties