Merge pull request #1 from json5/master

Merge from master

Author: mcraiha

Json5/Json5Number.cs

@@ -1,3 +1,5 @@
+using System.Globalization;
+
 namespace Json5
 {
     public class Json5Number : Json5Primitive
@@ -21,7 +23,7 @@ protected override object Value
 
         internal override string ToJson5String(string space, string indent)
         {
-            return this.value.ToString();
+            return this.value.ToString(CultureInfo.InvariantCulture);
         }
 
         public static implicit operator double(Json5Number value)

Json5/Parsing/Json5Lexer.cs

@@ -558,7 +558,8 @@ public Json5Token Read()
                     }
 
                     // Parse this value with BigInteger because ulong can only parse numbers up to 0xFFFFFFFFFFFFFFFF.
-                    return Token(Json5TokenType.Number, sign * (double)BigInteger.Parse(valueBuffer, NumberStyles.HexNumber), inputBuffer);
+                    // Add '0' to valueBuffer since otherwise it will be parsed as signed value (e.g. ff would be -1) 
+                    return Token(Json5TokenType.Number, sign * (double)BigInteger.Parse("0" + valueBuffer, NumberStyles.HexNumber), inputBuffer);
 
                 case State.String:
                     switch (r)