Enclose PEC parsing with using() to ensure file is closed

PesFile/PesFile.cs

@@ -32,7 +32,6 @@ namespace PesFile
 
     public class PesFile
     {
-        System.IO.BinaryReader fileIn;
         int imageWidth;
         int imageHeight;
         string _filename;
@@ -112,8 +111,12 @@ namespace PesFile
         private void OpenFile(string filename)
         {
             _filename = filename;
-            fileIn = new System.IO.BinaryReader(System.IO.File.Open(filename, System.IO.FileMode.Open, System.IO.FileAccess.Read));
 
+            // The using statements ensure fileIn is closed, no matter how the statement is exited.
+            using (System.IO.FileStream fileStreamIn = System.IO.File.Open(filename, System.IO.FileMode.Open, System.IO.FileAccess.Read))
+            {
+                using (System.IO.BinaryReader fileIn = new System.IO.BinaryReader(fileStreamIn))
+                {
                     string startFileSig = "";
                     for (int i = 0; i < 4; i++) // 4 bytes
                     {
@@ -124,7 +127,6 @@ namespace PesFile
                         // This is not a file that we can read
                         readyStatus = statusEnum.ParseError;
                         lastError = "Missing #PES at beginning of file";
-                fileIn.Close();
                         return;
                     }
 
@@ -134,29 +136,27 @@ namespace PesFile
                     {
                         versionString += fileIn.ReadChar();
                     }
-            if(!UInt16.TryParse(versionString, out pesVersion))
+                    if (!UInt16.TryParse(versionString, out pesVersion))
                     {
                         // This is not a file that we can read
                         readyStatus = statusEnum.ParseError;
                         lastError = "PES version is not the correct format";
-                fileIn.Close();
                         return;
                     }
 
                     int pecstart = fileIn.ReadInt32();
                     // Sanity check on PEC start position
-            if(fileIn.BaseStream.Length < (pecstart + 532))
+                    if (fileIn.BaseStream.Length < (pecstart + 532))
                     {
                         // This file is probably truncated
                         readyStatus = statusEnum.ParseError;
                         lastError = "File appears to be truncated (PEC section is beyond end of file)";
-                fileIn.Close();
                         return;
                     }
 
                     // Read number of colors in this design
                     fileIn.BaseStream.Position = pecstart + 48;
-            int numColors = fileIn.ReadByte() +1;
+                    int numColors = fileIn.ReadByte() + 1;
                     List<byte> colorList = new List<byte>();
                     for (int x = 0; x < numColors; x++)
                     {
@@ -319,9 +319,8 @@ namespace PesFile
                     translateStart.X = -minX;
                     translateStart.Y = -minY;
                     readyStatus = statusEnum.Ready;
-
-            // Close the file
-            fileIn.Close();
+                }
+            }
         }
 
         public int GetWidth()