Question

I have the code below. I’d like to convert all items in this list to uppercase.

Is there a way to do this in Linq ?

public class Person
{
    public string FirstName { get; set; }
    public string LastName { get; set; }
    public int Age { get; set; }
}

public class MyClass
{
    List<Person> myList = new List<Person>{ 
        new Person { FirstName = "Aaa", LastName = "BBB", Age = 2 },
        new Person{ FirstName = "Deé", LastName = "ève", Age = 3 }
    };
}

Update

I don’t want to loop or go field by field. Is there a way by reflection to uppercase the value for each property?

Answer 1

Why would you like to use LINQ?

Use List<T>.ForEach:

myList.ForEach(z =>
                {
                    z.FirstName = z.FirstName.ToUpper();
                    z.LastName = z.LastName.ToUpper();
                });

---

EDIT: no idea why you want to do this by reflection (I wouldn’t do this personally…), but here’s some code that’ll uppercase all properties that return a string. Do note that it’s far from being perfect, but it’s a base for you in case you really want to use reflection…:

public class Person
{
    public string FirstName { get; set; }

    public string LastName { get; set; }

    public int Age { get; set; }
}

public static class MyHelper
{
    public static void UppercaseClassFields<T>(T theInstance)
    {
        if (theInstance == null)
        {
            throw new ArgumentNullException();
        }

        foreach (var property in theInstance.GetType().GetProperties(BindingFlags.Public | BindingFlags.Instance))
        {
            var theValue = property.GetValue(theInstance, null);
            if (theValue is string)
            {
                property.SetValue(theInstance, ((string)theValue).ToUpper(), null);
            }
        }
    }

    public static void UppercaseClassFields<T>(IEnumerable<T> theInstance)
    {
        if (theInstance == null)
        {
            throw new ArgumentNullException();
        }

        foreach (var theItem in theInstance)
        {
            UppercaseClassFields(theItem);
        }
    }
}

public class Program
{
    private static void Main(string[] args)
    {
        List<Person> myList = new List<Person>{
            new Person { FirstName = "Aaa", LastName = "BBB", Age = 2 },
            new Person{ FirstName = "Deé", LastName = "ève", Age = 3 }
        };

        MyHelper.UppercaseClassFields<Person>(myList);

        Console.ReadLine();
    }
}