reflection

问题 Suppose you have the following abstract java class: public abstract class AbstractRequestHandler<I,O> { I input; O output; } and the following child classes hierarchy: public abstract class AbstractUserRequestHandler<I extends User,O> extends AbstractRequestHandler<I,O>{...} public abstract class AbstractUniversityRequestHandler<I extends UniversityUser> extends AbstractUserRequestHandler<I,String>{...} public class StudentRequestHandler extends AbstractUniversityRequestHandler<Student>{...}

问题 I have a discriminated union and I want to select a case based on a string (which is read from a JSON file). This is easy to do: type MyDU = A | B let str = "B" let myDU : MyDU = match str with | "A" -> MyDU.A | "B" -> MyDU.B | _ -> failwith "whatever" // val myDU : MyDU = B However, sometimes there are many cases, which would require a lot of typing. The Microsoft.FSharp.Reflection library allows me to get a UnionCaseInfo object: open Microsoft.FSharp.Reflection let myDUInfo : UnionCaseInfo

问题 I have a discriminated union and I want to select a case based on a string (which is read from a JSON file). This is easy to do: type MyDU = A | B let str = "B" let myDU : MyDU = match str with | "A" -> MyDU.A | "B" -> MyDU.B | _ -> failwith "whatever" // val myDU : MyDU = B However, sometimes there are many cases, which would require a lot of typing. The Microsoft.FSharp.Reflection library allows me to get a UnionCaseInfo object: open Microsoft.FSharp.Reflection let myDUInfo : UnionCaseInfo

问题 I have a bunch of regular, closed and opened types in my assembly. I have a query that I'm trying to rule out the open types from it class Foo { } // a regular type class Bar<T, U> { } // an open type class Moo : Bar<int, string> { } // a closed type var types = Assembly.GetExecutingAssembly().GetTypes().Where(t => ???); types.Foreach(t => ConsoleWriteLine(t.Name)); // should *not* output "Bar`2" Upon debugging the generic arguments of an open type, I found that their FullName is null (as

问题 I have a bunch of regular, closed and opened types in my assembly. I have a query that I'm trying to rule out the open types from it class Foo { } // a regular type class Bar<T, U> { } // an open type class Moo : Bar<int, string> { } // a closed type var types = Assembly.GetExecutingAssembly().GetTypes().Where(t => ???); types.Foreach(t => ConsoleWriteLine(t.Name)); // should *not* output "Bar`2" Upon debugging the generic arguments of an open type, I found that their FullName is null (as

问题 I have a bunch of regular, closed and opened types in my assembly. I have a query that I'm trying to rule out the open types from it class Foo { } // a regular type class Bar<T, U> { } // an open type class Moo : Bar<int, string> { } // a closed type var types = Assembly.GetExecutingAssembly().GetTypes().Where(t => ???); types.Foreach(t => ConsoleWriteLine(t.Name)); // should *not* output "Bar`2" Upon debugging the generic arguments of an open type, I found that their FullName is null (as

问题 I have a bunch of regular, closed and opened types in my assembly. I have a query that I'm trying to rule out the open types from it class Foo { } // a regular type class Bar<T, U> { } // an open type class Moo : Bar<int, string> { } // a closed type var types = Assembly.GetExecutingAssembly().GetTypes().Where(t => ???); types.Foreach(t => ConsoleWriteLine(t.Name)); // should *not* output "Bar`2" Upon debugging the generic arguments of an open type, I found that their FullName is null (as

问题 I have a bunch of regular, closed and opened types in my assembly. I have a query that I'm trying to rule out the open types from it class Foo { } // a regular type class Bar<T, U> { } // an open type class Moo : Bar<int, string> { } // a closed type var types = Assembly.GetExecutingAssembly().GetTypes().Where(t => ???); types.Foreach(t => ConsoleWriteLine(t.Name)); // should *not* output "Bar`2" Upon debugging the generic arguments of an open type, I found that their FullName is null (as

问题 I had the following line snippet of code that searches for a propery of an instance by name: var prop = Backend.GetType().GetProperty(fieldName); Now I want to ignore the case of fieldName, so I tried the following: var prop = Backend.GetType().GetProperty(fieldName, BindingFlags.IgnoreCase); ... No dice. Now prop won't find field names that have the exact case. Hence..... How do I use .Net reflection to search for a property by name ignoring case? 回答1: You need to specify BindingFlags.Public

问题 I am trying to create Delegate for reading/writing properties of unknown type of class at runtime. I have a generic class Main<T> and a method which looks like this: Delegate.CreateDelegate(typeof(Func<T, object>), get) where get is a MethodInfo of the property that should be read. The problem is that when the property returns int (I guess this happens for value types) the above code throws ArgumentException because the method cannot be bound. In case of string it works well. To solve the