在类型转换时常会遇到隐式转换和显式转换。那我们自定义的类型要如何去定义隐式转换和显式转换？我们来看一段代码
public class Rational { private Int32 _inner_int = 0; public Rational() { } public Rational(Int32 num) { this._inner_int = num; } public Int32 ToInt32() { return this._inner_int; } // Implicitly constructs and returns a Rational from an Int32 public static implicit operator Rational(Int32 num) { return new Rational(num); } // Explicitly returns an Int32 from a Rational public static explicit operator Int32(Rational r) { return r.ToInt32(); } public override string ToString() { //return base.ToString(); String s = String.Format("{0}", this._inner_int); return s; } } |
测试代码
class Program { static void Main(string[] args) { Rational r1 = 10; Console.WriteLine(r1); Int32 i = r1; Console.WriteLine(i); Console.ReadLine(); } } |
