Added dictionary<->string conversion and a safe dict that returns null if key is not found

BackupEssentials/BackupEssentials.csproj

@@ -96,6 +96,8 @@
     <Compile Include="TestingWindow.xaml.cs">
       <DependentUpon>TestingWindow.xaml</DependentUpon>
     </Compile>
+    <Compile Include="Utils\SafeDictionary.cs" />
+    <Compile Include="Utils\StringDictionarySerializer.cs" />
     <Compile Include="Utils\ProgramArgsParser.cs" />
     <Compile Include="Utils\ScheduledUpdate.cs" />
     <Compile Include="Utils\WindowsVersion.cs" />

BackupEssentials/Utils/SafeDictionary.cs

@@ -0,0 +1,20 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+
+namespace BackupEssentials.Utils{
+    class SafeDictionary<K,V> : Dictionary<K,V>{
+        public new V this[K key]{
+            get {
+                V value;
+                TryGetValue(key,out value);
+                return value;
+            }
+
+            set {
+                base[key] = value;
+            }
+        }
+    }
+}

BackupEssentials/Utils/StringDictionarySerializer.cs

@@ -0,0 +1,49 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+
+namespace BackupEssentials.Utils{
+    class StringDictionarySerializer{
+        public static string ToString(Dictionary<string,string> dict){
+            StringBuilder build = new StringBuilder();
+
+            foreach(KeyValuePair<string,string> kvp in dict){
+                build.Append(kvp.Key).Append((char)31).Append(kvp.Value).Append((char)31);
+            }
+
+            if (build.Length > 0)build.Remove(build.Length-1,1);
+            return build.ToString();
+        }
+        
+        public static string ToString(IObjectToDictionary obj){
+            SafeDictionary<string,string> dict = new SafeDictionary<string,string>();
+            obj.ToDictionary(dict);
+            return ToString(dict);
+        }
+
+        public static SafeDictionary<string,string> FromString(string data){
+            SafeDictionary<string,string> dict = new SafeDictionary<string,string>();
+            string key = null;
+
+            foreach(string part in data.Split((char)31)){
+                if (key == null)key = part;
+                else{
+                    dict.Add(key,part);
+                    key = null;
+                }
+            }
+
+            return dict;
+        }
+
+        public static void FromString(IObjectToDictionary obj, string data){
+            obj.FromDictionary(FromString(data));
+        }
+
+        public interface IObjectToDictionary{
+            void ToDictionary(SafeDictionary<string,string> dict);
+            void FromDictionary(SafeDictionary<string,string> dict);
+        }
+    }
+}