我见过很多人使用以下代码:
Type t = obj1.GetType();
if (t == typeof(int))
// Some code here
但我知道你也可以这样做:
if (obj1.GetType() == typeof(int))
// Some code here
或者这个:
if (obj1 is int)
// Some code here
就我个人而言,我觉得最后一个是最干净的,但我有什么遗漏吗?哪一个最好用,还是个人喜好?
性能测试类型of()与GetType():
using System;
namespace ConsoleApplication1
{
class Program
{
enum TestEnum { E1, E2, E3 }
static void Main(string[] args)
{
{
var start = DateTime.UtcNow;
for (var i = 0; i < 1000000000; i++)
Test1(TestEnum.E2);
Console.WriteLine(DateTime.UtcNow - start);
}
{
var start = DateTime.UtcNow;
for (var i = 0; i < 1000000000; i++)
Test2(TestEnum.E2);
Console.WriteLine(DateTime.UtcNow - start);
}
Console.ReadLine();
}
static Type Test1<T>(T value) => typeof(T);
static Type Test2(object value) => value.GetType();
}
}
调试模式下的结果:
00:00:08.4096636
00:00:10.8570657
释放模式下的结果:
00:00:02.3799048
00:00:07.1797128