144调用接口方法详解145接口方法的隐式和显式调用146泛型接口147泛型接口和接口约束148实现 144调用接口方法详解 145接口方法的隐式和显式调用 146泛型接口 147 泛型接口和接口约束 148实
145接口方法的隐式和显式调用
146泛型接口
147 泛型接口和接口约束
148实现具有多个方法名和签名的多个接口
149用显示接口方法实现改进编译时类型安全
class Program
{
public static void Main() {
SomeValueType sv new SomeValueType(5); Object o1 new object(); Int32 n sv.CompareTo(sv);//装箱操作 // n sv.CompareTo(o1);//编译通过出现运行时错误 OtherValueType ov new OtherValueType(5); Object o2 new object(); n ov.CompareTo(ov);//没有进行装箱操作 // n ov.CompareTo(o2);//编译时错误 Console.WriteLine(n); Console.ReadLine();
}
} //未使用EIMI internal struct SomeValueType : IComparable { private Int32 m_x; public SomeValueType(Int32 x) { m_x x; } public Int32 CompareTo(Object other) { return (m_x - ((SomeValueType)other).m_x); } } //使用EIMI internal struct OtherValueType : IComparable { private Int32 m_x; public OtherValueType(Int32 x){ m_x x; } public Int32 CompareTo(OtherValueType other) { return (m_x - other.m_x); } Int32 IComparable.CompareTo(Object other) { return CompareTo((OtherValueType)other); } } 1410谨慎使用显示接口方法实现
// //internal class Base : IComparable { // //显式接口方法 // Int32 IComparable.CompareTo(Object o) { // Console.WriteLine("Base.ComparaTo"); // return 0; // } //} //internal class Derived : Base,IComparable { // //接口实现的公共方法 // public Int32 CompareTo(Object o){ // Console.WriteLine("Derived.ComparaTo"); // //调用基类的CompareTo会导致错误 // //base.CompareTo(o); // return 0; // } //} //正确定义Base和Derived internal class Base : IComparable { //显式接口方法 Int32 IComparable.CompareTo(Object o) { Console.WriteLine("Bases IComparable ComparaTo"); return 0; } //基类的虚方法 public virtual Int32 CompareTo(Object o) { Console.WriteLine("Bases virtual ComparaTo"); return 0; } } internal class Derived : Base, IComparable { //也是接口实现的公共方法 public override Int32 CompareTo(Object o) { Console.WriteLine("Derived.ComparaTo"); return base.CompareTo(o); } } 1411设计基类还是接口