Code fixes from Sonarcloud analysis (#17)

Author: josesimoes

System.IO.Streams/MemoryStream.cs

@@ -16,15 +16,15 @@ public class MemoryStream : Stream
         // Either allocated internally or externally.
         private byte[] _buffer;
         // For user-provided arrays, start at this origin
-        private int _origin;
+        private readonly int _origin;
         // read/write head.
         private int _position;
         // Number of bytes within the memory stream
         private int _length;
         // length of usable portion of buffer for stream
         private int _capacity;
         // User-provided buffers aren't expandable.
-        private bool _expandable;
+        private readonly bool _expandable;
         // Is this stream open or closed?
         private bool _isOpen;
 

System.IO.Streams/StreamReader.cs

@@ -205,7 +205,7 @@ public override int Peek()
         /// </remarks>
         public override int Read()
         {
-            int byteUsed, charUsed;
+            int byteUsed;
 
             while (true)
             {
@@ -218,7 +218,7 @@ public override int Read()
                     1,
                     false,
                     out byteUsed,
-                    out charUsed,
+                    out System.Int32 charUsed,
                     out _);
 
                 _curBufPos += byteUsed;

System.IO.Streams/StreamWriter.cs

@@ -90,13 +90,19 @@ protected override void Dispose(bool disposing)
                             Flush();
                         }
                     }
-                    catch { }
+                    catch
+                    {
+                        // empty on purpose to catch any exceptions during call to Flush
+                    }
 
                     try
                     {
                         BaseStream.Close();
                     }
-                    catch { }
+                    catch
+                    {
+                        // empty on purpose to catch any exceptions during call to Close
+                    }
                 }
 
                 BaseStream = null;

System.IO.Streams/TextReader.cs

@@ -127,7 +127,8 @@ public virtual int ReadBlock(char[] buffer, int index, int count)
 
             do
             {
-                n += (i = Read(buffer, index + n, count - n));
+                i = Read(buffer, index + n, count - n);
+                n += i;
             } while (i > 0 && n < count);
 
             return n;

System.IO.Streams/TextWriter.cs

@@ -150,7 +150,7 @@ public virtual void Write(char[] buffer, int index, int count)
         /// <param name="value">The <see cref="bool"/> value to write.</param>
         public virtual void Write(bool value)
         {
-            Write(value);
+            Write(value.ToString());
         }
 
         /// <summary>