added file lock check to BaseEntity

SpatialConnect.Entity/BaseEntity.cs

@@ -1,6 +1,7 @@
 using Newtonsoft.Json;
 using System.IO;
-
+using System.Threading;
+
 namespace SpatialConnect.Entity
 {
     public abstract class BaseEntity
@@ -14,7 +15,37 @@ public void Write(string path)
         {
             string json = JsonConvert.SerializeObject(this);
 
+            while (IsFileOpen(path))
+            {
+                Thread.Sleep(1000);
+            }
+
             File.WriteAllText(path, json);
         }
+
+        public bool IsFileOpen(string path)
+        {
+            FileStream stream = null;
+
+            try 
+            {
+                stream = File.OpenRead(path);
+            }
+            catch (IOException ex)
+            {
+                _log.Debug("file locked, will retry (File: " + path + ")");
+
+                return true;
+            }
+            finally
+            {
+                if (stream != null)
+                {
+                    stream.Close();
+                }
+            }
+
+            return false;
+        }
     }
 }