下面是一个代码示例和问题，请注意我不能使用 C# 4.0 和 dynamic 关键字。
static class TestClass
{
static void Main(string[] args)
{
Object o = "Previous value";
Test(ref o);
Trace.WriteLine(o);
}
static public void Test<T>(ref T obj)
{
// The goal is to somehow invoke Test2 with the real type of obj, i.e the type in obj.GetType()
// 1st try:
Test2(ref obj); // This doesn't work because the type in Test2 will be the same as T here.
// 2nd try:
MethodInfo mi = typeof(TestClass).GetMethod("Test2");
mi = mi.MakeGenericMethod(new Type[] { obj.GetType() });
mi.Invoke(null, new Object[] { obj }); // obj is no longer by reference so we need to store the object array and copy back the result after the call
// 3rd try, successful implementation by the smartest mind of stack overflow :)
}
static public void Test2<T>(ref T s)
{
if (typeof(T) == typeof(String))
{
s = (T)(Object)"Hello world!";
}
}
}
我还尝试了一些使用 Delegate.CreateDelegate 的方法，但没有成功。 这有可能吗？
编辑:我不害怕使用动态方法(和 MSIL 汇编程序)，但我在这方面的知识非常有限。
Edit2:这是一个更接近我真正尝试做的例子:
public static class TypeHandler<T>
{
public delegate void ProcessDelegate(ref T value);
public static readonly ProcessDelegate Process = Init();
private static ProcessDelegate Init()
{
// Do lot's of magic stuff and returns a suitable delegate depending on the type
return null;
}
}
static class TestClass
{
static public void Main(string[] args)
{
Object o = "Previous value";
Test(ref o);
Trace.WriteLine(o);
}
static public void Test<T>(ref T obj)
{
if (obj is T)
{
// Optimized, common case
TypeHandler<T>.Process(ref obj);
return;
}
Type t = obj.GetType();
// How to call the delegate found in TypeHandler<t>.Process ? (I can get delegate but I can't call it).
}
}
最佳答案
您的评论看起来您已经了解如何去做:
MethodInfo mi = typeof(TestClass).GetMethod("Test2");
mi = mi.MakeGenericMethod(new Type[] { obj.GetType() });
object[] args = new object[] { obj };
mi.Invoke(null, args);
obj = (T) args[0];
这实际上只是将您的评论转化为代码。这会不会以某种方式无法满足您的要求？
关于c# - 使用 System.Type 中的泛型类型调用泛型方法，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/8357454/