Extensions/NameValueCollectionExtensions.cs

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using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Collections.Specialized;


namespace ComLib.Extensions
{
    /// <summary>
    /// Extension classes for NameValueCollection.
    /// </summary>
    public class NameValueExtensions
    {
        /// <summary>
        /// Gets the value associated w/ the key, if it's empty returns the default value.
        /// </summary>
        /// <param name="collection"></param>
        /// <param name="key"></param>
        /// <param name="defaultValue"></param>
        /// <returns></returns>
        public static string GetOrDefault(NameValueCollection collection, string key, string defaultValue)
        {
            if (collection == null) return defaultValue;

            string val = collection[key];
            if (string.IsNullOrEmpty(val))
                return defaultValue;

            return val;
        }


        /// <summary>
        /// Gets the value associated w/ the key and convert it to the correct Type, if empty returns the default value.
        /// </summary>
        /// <typeparam name="T">The type to convert the value to.</typeparam>
        /// <param name="collection">Collection.</param>
        /// <param name="key">The key representing the value to get.</param>
        /// <param name="defaultValue">Value to return if the key has an empty value.</param>
        /// <returns></returns>
        public static T GetOrDefault<T>(NameValueCollection collection, string key, T defaultValue)
        {
            if (collection == null) return defaultValue;

            string val = collection[key];
            if (string.IsNullOrEmpty(val))
                return defaultValue;

            return Converter.ConvertTo<T>(val);
        }
    }
}