Make InputFieldRef helper, InteractiveString and IOUtility

src/Core/Utility/IOUtility.cs

@@ -0,0 +1,29 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace UnityExplorer
+{
+    public static class IOUtility
+    {
+        public static string EnsureValid(string path)
+        {
+            path = RemoveInvalidChars(path);
+
+            var dir = Path.GetDirectoryName(path);
+
+            if (!Directory.Exists(dir))
+                Directory.CreateDirectory(dir);
+
+            return path;
+        }
+
+        public static string RemoveInvalidChars(string path)
+        {
+            return string.Concat(path.Split(Path.GetInvalidPathChars()));
+        }
+    }
+}