Question

I have a string such as “Int”, “Double”, “DateTime” etc. How do I get the fully qualified name from this string?

Answer 1

It’s worth bearing in mind that int isn’t a type. It’s an alias provided by C# for the type System.Int32. Bearing that in mind, and assuming you only care about core types, you can try:

var typeName = "DateTime";

var systemTypesAssembly = Assembly.Load("mscorlib");

var type = (from t in systemTypesAssembly.GetTypes()
           where t.Name == typeName
           select t).FirstOrDefault();

Console.WriteLine(type.FullName);

As I said, this will not work for Int, but would work for Int32 which is the type it’s aliased to. This code also contains no error handling for where, for example, no type is found in mscorlib that matches the one you’ve entered in typeName