Refactor StringExtensions

Author: Shane32

QRCoder/Framework4.0Methods/String4Methods.cs renamed to QRCoder/Extensions/StringExtensions.cs

@@ -1,23 +1,21 @@
-using System;
-
 namespace QRCoder
 {
-    internal static class String40Methods
+    internal static class StringExtensions
     {
         /// <summary>
         /// Indicates whether the specified string is null, empty, or consists only of white-space characters.
         /// </summary>
         /// <returns>
         ///   <see langword="true"/> if the <paramref name="value"/> is null, empty, or white space; otherwise, <see langword="false"/>.
         /// </returns>
-        public static bool IsNullOrWhiteSpace(String value)
+        public static bool IsNullOrWhiteSpace(this string value)
         {
 #if NET35
             if (value == null) return true;
 
             for (int i = 0; i < value.Length; i++)
             {
-                if (!Char.IsWhiteSpace(value[i])) return false;
+                if (!char.IsWhiteSpace(value[i])) return false;
             }
 
             return true;

QRCoder/PayloadGenerator.cs

@@ -2030,7 +2030,7 @@ private string TimeToString()
 
             private void ProcessCommonFields(StringBuilder sb)
             {
-                if (String40Methods.IsNullOrWhiteSpace(Secret))
+                if (Secret.IsNullOrWhiteSpace())
                 {
                     throw new Exception("Secret must be a filled out base32 encoded string");
                 }
@@ -2039,7 +2039,7 @@ private void ProcessCommonFields(StringBuilder sb)
                 string escapedLabel = null;
                 string label = null;
 
-                if (!String40Methods.IsNullOrWhiteSpace(Issuer))
+                if (!Issuer.IsNullOrWhiteSpace())
                 {
                     if (Issuer.Contains(":"))
                     {
@@ -2048,7 +2048,7 @@ private void ProcessCommonFields(StringBuilder sb)
                     escapedIssuer = Uri.EscapeDataString(Issuer);
                 }
 
-                if (!String40Methods.IsNullOrWhiteSpace(Label))
+                if (!Label.IsNullOrWhiteSpace())
                 {
                     if (Label.Contains(":"))
                     {