C# typeof()实例详解
typeof(C# 参考)
用于获取类型的 System.Type 对象。typeof 表达式采用以下形式:
System.Type type = typeof(int);
备注
若要获取表达式的运行时类型,可以使用 .NET Framework 方法 GetType,如下所示:
int i = 0; System.Type type = i.GetType();
typeof 运算符也能用于公开的泛型类型。具有不止一个类型参数的类型的规范中必须有适当数量的逗号。不能重载 typeof 运算符。
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示例 // cs_operator_typeof.cs using System; using System.Reflection; public class SampleClass { public int sampleMember; public void SampleMethod() {} static void Main() { Type t = typeof (SampleClass); // Alternatively, you could use // SampleClass obj = new SampleClass(); // Type t = obj.GetType(); Console.WriteLine( "Methods:" ); MethodInfo[] methodInfo = t.GetMethods(); foreach (MethodInfo mInfo in methodInfo) Console.WriteLine(mInfo.ToString()); Console.WriteLine( "Members:" ); MemberInfo[] memberInfo = t.GetMembers(); foreach (MemberInfo mInfo in memberInfo) Console.WriteLine(mInfo.ToString()); } } 输出 Methods: Void SampleMethod() System.Type GetType() System.String ToString() Boolean Equals(System.Object) Int32 GetHashCode() Members: Void SampleMethod() System.Type GetType() System.String ToString() Boolean Equals(System.Object) Int32 GetHashCode() Void .ctor() Int32 sampleMember 此示例使用 GetType 方法确定用来包含数值计算的结果的类型。这取决于结果数字的存储要求。 // cs_operator_typeof2.cs using System; class GetTypeTest { static void Main() { int radius = 3; Console.WriteLine( "Area = {0}" , radius * radius * Math.PI); Console.WriteLine( "The type is {0}" , (radius * radius * Math.PI).GetType() ); } } 输出 Area = 28.2743338823081 The type is System.Double |