Question

For an application I’m working on I’m trying to display a template that will show what the parameters for a (runtime-determined) method look like. The test case I’m working on should show “PERSON = (FIRST = first; LAST = last);”, where the parameter named Person has type Name, and Name has two properties, First and Last. The following code instead shows “PERSON = ();”.

GetNestedTypes is not returning anything, any ideas why?

public static string GetParameterTemplate(MethodInfo method)
{
    StringBuilder output = new StringBuilder();
    foreach (ParameterInfo pi in method.GetParameters())
    {
        output.Append(parameterTemplateHelper(pi.Name, pi.ParameterType));
    }
    return output.ToString();
}

private static string parameterTemplateHelper(string pName, Type pType)
{
    string key = pName.ToUpper();
    string value = "";

    if (pType.IsPrimitive)
    {
        // it's a primitive
        value = pName.ToLower();
    }
    else if (pType.IsArray)
    {
        if (pType.GetElementType().IsPrimitive)
        {
            // array of primitives
            value = String.Format("{0}1, {0}2;", pName.ToLower());
        }
        else
        {
            // array of objects
            StringBuilder sb = new StringBuilder();
            foreach (Type t in pType.GetElementType().GetNestedTypes(BindingFlags.Public | BindingFlags.NonPublic))
            {
                sb.Append(parameterTemplateHelper(t.Name, t));
            }
            value = String.Format("({0}), ({0});", sb);
        }
    }
    else
    {
        // object
        StringBuilder sb = new StringBuilder();
        Type[] junk = pType.GetNestedTypes(BindingFlags.Public | BindingFlags.NonPublic);
        foreach (Type t in pType.GetNestedTypes())
        {
            sb.Append(parameterTemplateHelper(t.Name, t));
        }
        value = String.Format("({0});", sb.ToString());
    }

    string output = key + " = " + value.ToString();
    return output;
}

Answer 1

Your code is looking for nested types – that is, other types declared within Person. That’s not at all the same as looking for properties within Person.

Here’s a class with nested types:

public class Name
{
    public class Nested1 {}
    public class Nested2 {}
}

Here’s a class with properties:

public class Name
{
    public string Name { get; set; }
    public string Name { get; set; }
}

My guess is that your situation is much more like the second one than the first… so use Type.GetProperties instead of Type.GetNestedTypes.