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copied!<p>I don't think what you're asking is possible. If your code is receiving a string that represents the generic type parameter, the type it represents can only be determined at runtime. However, generic type parameters should be specified at compile time.</p> <p>I think you'll have to instead receive the type of entity as a generic type parameter if you want to use it as a type parameter of the return type:</p> <pre><code>public IRepository<TEntity> MakeRepository<TEntity>() where TEntity : class { var repo = new TradeSiftRepository<TEntity>(new UnitOfWork()); return repo; } IRepository<User> userRepository = MakeRepository<User>(); </code></pre> <p>If you definitely want to receive the entity type name as a string, the responsibility of casting the result to the real type at compile time should be done by calling code, since the calling code is what specifies the type:</p> <pre><code>public object MakeRepository(string entityTypeName) { Assembly common = Assembly.LoadFrom(@"CommonLibrary.dll"); Type entityType = common.GetType(entityTypeName); Type repoType = typeof(TradeSiftRepository<>).MakeGenericType(entityType); var repo = Activator.CreateInstance(repoType, new UnitOfWork()); return repo; } IRepository<User> userRepository = (IRepository<User>)MakeRepository("User"); </code></pre> <p>However, the above code can be simplified by using the generic version of the method; there is less duplication. If the calling code also doesn't know what type it's asking for, I think you're out of options.</p> <p>One possible work-around is to return the dynamic type, which would leave the calling code to assume it has an object of the type its author wants:</p> <pre><code>public dynamic MakeRepository(string entityTypeName) { Assembly common = Assembly.LoadFrom(@"CommonLibrary.dll"); Type entityType = common.GetType(entityTypeName); Type repoType = typeof(TradeSiftRepository<>).MakeGenericType(entityType); var repo = Activator.CreateInstance(repoType, new UnitOfWork()); return repo; } dynamic userRepository = MakeRepository("ConsoleApplication1.User"); User user = userRepository.FindById(1); </code></pre>

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