ArgumentValidation

ArgumentValidation.cs

using System;
using JetBrains.Annotations;

namespace Helpers
{
    public static class ArgumentValidation
    {
        public static void ThrowIfNull<T>([ValidatedNotNull] [NoEnumeration] T argument)
            where T : class
        {
            ThrowIfNull(nameof(argument), argument);
        }

        /// <summary>
        ///     Throws if null.
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <param name="name">The name of the argument.</param>
        /// <param name="argument">The argument value.</param>
        /// <exception cref="System.ArgumentNullException">The argument is null.</exception>
        public static void ThrowIfNull<T>(string name, [ValidatedNotNull] [NoEnumeration] T argument)
            where T : class
        {
            if (argument == null)
                throw new ArgumentNullException(name);
        }

        public static T ValidatedNotNull<T>([ValidatedNotNull] [NoEnumeration] this T argument, string name)
            where T : class
        {
            ThrowIfNull(name, argument);
            return argument;
        }

        public static string ValidatedNotNullOrEmpty([ValidatedNotNull] [NoEnumeration] this string argument,
            string name)
        {
            ThrowIfNullOrEmpty(name, argument);
            return argument;
        }

        /// <summary>
        ///     Throws if null or empty.
        /// </summary>
        /// <param name="argument">The argument.</param>
        /// <exception cref="System.ArgumentNullException">The argument is null or is empty.</exception>
        public static void ThrowIfNullOrEmpty([ValidatedNotNull] string argument)
        {
            ThrowIfNullOrEmpty(nameof(argument), argument);
        }

        public static void ThrowIfNullOrEmpty(string name, [ValidatedNotNull] string argument)
        {
            if (string.IsNullOrEmpty(argument))
                throw new ArgumentNullException(name);
        }
    }

    // Tells CodeAnalysis that this argument is being validated 
    // to be not null. Great for guard methods.
    [AttributeUsage(AttributeTargets.Parameter)]
    internal sealed class ValidatedNotNullAttribute : Attribute
    {
    }
}