Hello everybody,
today I want to document few features of System.Reflection namespace.
It has following important types:
Type ( with methods GetType, GetMemberInfo, GetPropertyInfo, GetFieldInfo ), Activator ( with method CreateInstance ), Assembly ( Load, LoadFrom, GetTypes, GetName, GetFiles ), ILGenerator ( Emit ).
Some code fragments for reflection
var lst = new List<double>();
Type listType = typeof(List<double>);
Type[] pars = {typeof(double)};
MethodInfo addMeth = listType.GetMethod("Add", pars);
addMethod.Invoke(lst, new object[] {8.3});
Create an isntace of type:
public static Type GetType(string typeName)
public static object CreateInstance(Type type)
How to work with interfaces
public static Assembly LoadFrom(string assemblyFile); // load assembly
public IEnumberable<Type> ExportedTypes {get; }// Get types exposed on an Assembly
public bool IsAssinableFrom( Type c ); //check if type implements interface
public bool IsSubClassOf(Type c); // check if type inherits another type
public bool IsClass {get; } // check if type is a class
Fully-Qualified type name
Suppose you want to create some instance of interface implementation. You can see following Fully-qualified name:
Repository.Interface.IRepository`2[SomeClass1, System.String]
Question: for what stands 2 after back tick symbol? 2 says the following: Repository.Interface.IRepository has 2 generic type parameters.
Sample of search and Load
IEnumerable<string> assemblyFiles = Directory.EnumerateFiles(assemblyPath, "*.dll", SearchOption.TopDirectoryOnly);
foreach (string assemblyFile in assemblyFiles)
{
Assembly assembly = Assembly.LoadFrom(assemblyFile);
foreach (Type type in assembly.ExportedTypes)
{
if (type.IsClass && typeof(ISomeInterface).IsAssignableFrom(type))
{
ISomeInterface interfaceInstance = Activator.CreateInstance(type) as ISomeInterface;
implementations.Add(new DynamicOrderRule(interfaceInstance, type.FullName, type.Assembly.GetName().Name));
}
}
}