Added string formatting options to ToQuantity

readme.md

@@ -354,6 +354,14 @@ You can also pass a second argument, `ShowQuantityAs`, to `ToQuantity` to specif
 "case".ToQuantity(5, ShowQuantityAs.None) => "cases"
 ```
 
+There is also an overload that allows you to format the number. You can pass in the format and the culture to be used.
+
+```C#
+"dollar".ToQuantity(2, "C0", new CultureInfo("en-US")) => "$2 dollars"
+"dollar".ToQuantity(2, "C2", new CultureInfo("en-US")) => "$2.00 dollars"
+"cases".ToQuantity(12000, "N0") => "12,000 cases"
+```
+
 ####<a id="ordinalize">Ordinalize</a>
 `Ordinalize` turns a number into an ordinal string used to denote the position in an ordered sequence such as 1st, 2nd, 3rd, 4th: 
 

src/Humanizer.Tests/ApiApprover/PublicApiApprovalTest.approve_public_api.approved.txt

@@ -338,6 +338,7 @@ public class To
 public class ToQuantityExtensions
 {
     public string ToQuantity(string input, int quantity, Humanizer.ShowQuantityAs showQuantityAs) { }
+    public string ToQuantity(string input, int quantity, string format, System.IFormatProvider formatProvider) { }
 }
 
 public class Truncator

src/Humanizer.Tests/ToQuantityTests.cs

@@ -1,4 +1,6 @@
-using Xunit;
+using System;
+using System.Globalization;
+using Xunit;
 using Xunit.Extensions;
 
 namespace Humanizer.Tests
@@ -79,5 +81,38 @@ public void ToQuantityWords(string word, int quatity, string expected)
         {
             Assert.Equal(expected, word.ToQuantity(quatity, ShowQuantityAs.Words));
         }
+
+        [Theory]
+        [InlineData("case", 0, null, "0 cases")]
+        [InlineData("case", 1, null, "1 case")]
+        [InlineData("case", 2, null, "2 cases")]
+        [InlineData("case", 1, "N0", "1 case")]
+        [InlineData("case", 2, "N0", "2 cases")]
+        [InlineData("case", 123456, "N0", "123,456 cases")]
+        [InlineData("case", 123456, "N2", "123,456.00 cases")]
+        [InlineData("dollar", 0, "C0", "$0 dollars")]
+        [InlineData("dollar", 1, "C0", "$1 dollar")]
+        [InlineData("dollar", 2, "C0", "$2 dollars")]
+        [InlineData("dollar", 2, "C2", "$2.00 dollars")]
+        public void ToQuantityWordsWithCurrentCultureFormatting(string word, int quantity, string format, string expected)
+        {
+            Assert.Equal(expected, word.ToQuantity(quantity, format));
+        }
+
+        [Theory]
+        [InlineData("case", 0, "N0", "it-IT", "0 cases")]
+        [InlineData("case", 1, "N0", "it-IT", "1 case")]
+        [InlineData("case", 2, "N0", "it-IT", "2 cases")]
+        [InlineData("case", 1234567, "N0", "it-IT", "1.234.567 cases")]
+        [InlineData("case", 1234567, "N2", "it-IT", "1.234.567,00 cases")]
+        [InlineData("euro", 0, "C0", "es-ES", "0 € euros")]
+        [InlineData("euro", 1, "C0", "es-ES", "1 € euro")]
+        [InlineData("euro", 2, "C0", "es-ES", "2 € euros")]
+        [InlineData("euro", 2, "C2", "es-ES", "2,00 € euros")]
+        public void ToQuantityWordsWithCustomCultureFormatting(string word, int quantity, string format, string cultureCode, string expected)
+        {
+            var culture = new CultureInfo(cultureCode);
+            Assert.Equal(expected, word.ToQuantity(quantity, format, culture), StringComparer.Create(culture, false));
+        }
     }
 }

src/Humanizer/ToQuantityExtensions.cs

@@ -1,4 +1,5 @@
-namespace Humanizer
+using System;
+namespace Humanizer
 {
     /// <summary>
     /// Enumerates the ways of displaying a quantity value when converting
@@ -44,6 +45,29 @@ public static class ToQuantityExtensions
         /// </example>
         /// <returns></returns>
         public static string ToQuantity(this string input, int quantity, ShowQuantityAs showQuantityAs = ShowQuantityAs.Numeric)
+        {
+            return input.ToQuantity(quantity, showQuantityAs, format: null, formatProvider: null);
+        }
+
+        /// <summary>
+        /// Prefixes the provided word with the number and accordingly pluralizes or singularizes the word
+        /// </summary>
+        /// <param name="input">The word to be prefixes</param>
+        /// <param name="quantity">The quantity of the word</param>
+        /// <param name="format">A standard or custom numeric format string.</param>
+        /// <param name="formatProvider">An object that supplies culture-specific formatting information.</param>
+        /// <example>
+        /// "request".ToQuantity(0) => "0 requests"
+        /// "request".ToQuantity(10000, format: "N0") => "10,000 requests"
+        /// "request".ToQuantity(1, format: "N0") => "1 request"
+        /// </example>
+        /// <returns></returns>
+        public static string ToQuantity(this string input, int quantity, string format, IFormatProvider formatProvider = null)
+        {
+            return input.ToQuantity(quantity, showQuantityAs: ShowQuantityAs.Numeric, format: format, formatProvider: formatProvider);
+        }
+
+        private static string ToQuantity(this string input, int quantity, ShowQuantityAs showQuantityAs = ShowQuantityAs.Numeric, string format = null, IFormatProvider formatProvider = null)
         {
             var transformedInput = quantity == 1
                 ? input.Singularize(Plurality.CouldBeEither)
@@ -53,7 +77,7 @@ public static string ToQuantity(this string input, int quantity, ShowQuantityAs
                 return transformedInput;
 
             if (showQuantityAs == ShowQuantityAs.Numeric)
-                return string.Format("{0} {1}", quantity, transformedInput);
+                return string.Format(formatProvider, "{0} {1}", quantity.ToString(format, formatProvider), transformedInput);
 
             return string.Format("{0} {1}", quantity.ToWords(), transformedInput);
         }