Added Base64 string value converter

Author: jamesmcroft

src/MADE.Data.Converters/Extensions/StringExtensions.cs

@@ -4,7 +4,9 @@
 namespace MADE.Data.Converters.Extensions
 {
     using System;
+    using System.IO;
     using System.Text;
+    using System.Threading.Tasks;
 
     /// <summary>
     /// Defines a collection of extensions for string values.
@@ -112,6 +114,21 @@ public static string FromBase64(this string base64Value, Encoding encoding = def
             return encoding.GetString(Convert.FromBase64String(base64Value));
         }
 
+        /// <summary>
+        /// Converts a string value to a <see cref="MemoryStream"/>.
+        /// </summary>
+        /// <param name="value">The value to convert.</param>
+        /// <returns>A <see cref="MemoryStream"/> representing the string value.</returns>
+        public static async Task<MemoryStream> ToMemoryStreamAsync(this string value)
+        {
+            var stream = new MemoryStream();
+            var writer = new StreamWriter(stream);
+            await writer.WriteAsync(value);
+            await writer.FlushAsync();
+            stream.Position = 0;
+            return stream;
+        }
+
         /// <summary>
         /// Converts a string value to an integer.
         /// </summary>

src/MADE.Data.Converters/StringToBase64StringValueConverter.cs

@@ -0,0 +1,48 @@
+// MADE Apps licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+namespace MADE.Data.Converters
+{
+    using System.Text;
+    using MADE.Data.Converters.Extensions;
+
+    /// <summary>
+    /// Defines a value converter from <see cref="string"/> to Base64 <see cref="string"/> with an optional Encoding parameter.
+    /// </summary>
+    public partial class StringToBase64StringValueConverter : IValueConverter<string, string>
+    {
+        /// <summary>
+        /// Converts the <paramref name="value">value</paramref> to the Base64 <see cref="string"/>.
+        /// </summary>
+        /// <param name="value">
+        /// The value to convert.
+        /// </param>
+        /// <param name="parameter">
+        /// The optional <see cref="Encoding"/> parameter used to help with conversion.
+        /// </param>
+        /// <returns>
+        /// The converted Base64 <see cref="string"/> object.
+        /// </returns>
+        public string Convert(string value, object parameter = default)
+        {
+            return value.ToBase64(parameter as Encoding ?? Encoding.UTF8);
+        }
+
+        /// <summary>
+        /// Converts the Base64 <paramref name="value">value</paramref> back to the original <see cref="string"/> value.
+        /// </summary>
+        /// <param name="value">
+        /// The value to convert.
+        /// </param>
+        /// <param name="parameter">
+        /// The optional <see cref="Encoding"/> parameter used to help with conversion.
+        /// </param>
+        /// <returns>
+        /// The converted <see cref="string"/> object.
+        /// </returns>
+        public string ConvertBack(string value, object parameter = default)
+        {
+            return value.FromBase64(parameter as Encoding ?? Encoding.UTF8);
+        }
+    }
+}