update ca2213

Author: gewarren

docs/code-quality/ca2213-disposable-fields-should-be-disposed.md

@@ -1,6 +1,6 @@
 ---
 title: "CA2213: Disposable fields should be disposed"
-ms.date: 11/04/2016
+ms.date: 11/05/2018
 ms.prod: visual-studio-dev15
 ms.technology: vs-ide-code-analysis
 ms.topic: reference
@@ -27,26 +27,33 @@ ms.workload:
 |Breaking Change|Non Breaking|
 
 ## Cause
- A type that implements <xref:System.IDisposable?displayProperty=fullName> declares fields that are of types that also implement <xref:System.IDisposable>. The <xref:System.IDisposable.Dispose%2A> method of the field is not called by the <xref:System.IDisposable.Dispose%2A> method of the declaring type.
+
+A type that implements <xref:System.IDisposable?displayProperty=fullName> declares fields that are of types that also implement <xref:System.IDisposable>. The <xref:System.IDisposable.Dispose%2A> method of the field is not called by the <xref:System.IDisposable.Dispose%2A> method of the declaring type.
 
 ## Rule description
- A type is responsible for disposing of all its unmanaged resources; this is accomplished by implementing <xref:System.IDisposable>. This rule checks to see whether a disposable type `T` declares a field `F` that is an instance of a disposable type `FT`. For each field `F`, the rule attempts to locate a call to `FT.Dispose`. The rule searches the methods called by `T.Dispose`, and one level lower (the methods called by the methods called by `FT.Dispose`).
+
+A type is responsible for disposing of all its unmanaged resources. Rule CA2213 checks to see whether a disposable type (that is, one that implements <xref:System.IDisposable>) `T` declares a field `F` that is an instance of a disposable type `FT`. For each field `F` that's assigned a locally created object within the methods or initializers of the containing type `T`, the rule attempts to locate a call to `FT.Dispose`. The rule searches the methods called by `T.Dispose` and one level lower (that is, the methods called by the methods called by `FT.Dispose`).
+
+> [!NOTE]
+> Rule CA2213 fires only for fields that are assigned a locally created disposable object within the containing type's methods and initializers. If the object is created or assigned outside of type `T`, the rule does not fire. This reduces noise for cases where the containing type doesn't own the responsibility for disposing of the object.
 
 ## How to fix violations
- To fix a violation of this rule, call <xref:System.IDisposable.Dispose%2A> on fields that are of types that implement <xref:System.IDisposable> if you are responsible for allocating and releasing the unmanaged resources held by the field.
+
+To fix a violation of this rule, call <xref:System.IDisposable.Dispose%2A> on fields that are of types that implement <xref:System.IDisposable>.
 
 ## When to suppress warnings
- It is safe to suppress a warning from this rule if you are not responsible for releasing the resource held by the field, or if the call to <xref:System.IDisposable.Dispose%2A> occurs at a deeper calling level than the rule checks.
+
+It is safe to suppress a warning from this rule if you're not responsible for releasing the resource held by the field, or if the call to <xref:System.IDisposable.Dispose%2A> occurs at a deeper calling level than the rule checks.
 
 ## Example
- The following example shows a type `TypeA` that implements <xref:System.IDisposable> (`FT` in the previosu discussion).
 
- [!code-csharp[FxCop.Usage.IDisposablePattern#1](../code-quality/codesnippet/CSharp/ca2213-disposable-fields-should-be-disposed_1.cs)]
+The following snippet shows a type `TypeA` that implements <xref:System.IDisposable>.
 
-## Example
- The following example shows a type `TypeB` that violates this rule by declaring a field `aFieldOfADisposableType` (`F` in the previous discussion) as a disposable type (`TypeA`) and not calling <xref:System.IDisposable.Dispose%2A> on the field. `TypeB` corresponds to `T` in the previous discussion.
+[!code-csharp[FxCop.Usage.IDisposablePattern#1](../code-quality/codesnippet/CSharp/ca2213-disposable-fields-should-be-disposed_1.cs)]
+
+The following snippet shows a type `TypeB` that violates rule CA2213 by declaring a field `aFieldOfADisposableType` as a disposable type (`TypeA`) and not calling <xref:System.IDisposable.Dispose%2A> on the field.
 
- [!code-csharp[FxCop.Usage.IDisposableFields#1](../code-quality/codesnippet/CSharp/ca2213-disposable-fields-should-be-disposed_2.cs)]
+[!code-csharp[FxCop.Usage.IDisposableFields#1](../code-quality/codesnippet/CSharp/ca2213-disposable-fields-should-be-disposed_2.cs)]
 
 ## See also
 

docs/code-quality/codesnippet/CSharp/ca2213-disposable-fields-should-be-disposed_1.cs

@@ -1,13 +1,12 @@
-using System;  
+using System;
 
 namespace UsageLibrary
 {
-    public class  TypeA :IDisposable
+    public class  TypeA : IDisposable
     {
-     
-        protected virtual void Dispose(bool disposing) 
+        protected virtual void Dispose(bool disposing)
         {
-            if (disposing) 
+            if (disposing)
             {
                 // Dispose managed resources
             }
@@ -17,11 +16,8 @@ protected virtual void Dispose(bool disposing)
 
         public void Dispose()
         {
-
-                Dispose(true);
-
-                GC.SuppressFinalize(this);
-
+            Dispose(true);
+            GC.SuppressFinalize(this);
         }
 
         // Disposable types implement a finalizer.

docs/code-quality/codesnippet/CSharp/ca2213-disposable-fields-should-be-disposed_2.cs

@@ -1,4 +1,4 @@
-using System;  
+using System;
 
 namespace UsageLibrary
 {
@@ -8,21 +8,21 @@ public class  TypeB : IDisposable
       TypeA aFieldOfADisposableType = new TypeA();
       private bool disposed = false;
 
-      protected virtual void Dispose(bool disposing) 
+      protected virtual void Dispose(bool disposing)
       {
-         if (!disposed) 
+         if (!disposed)
          {
             // Dispose of resources held by this instance.
 
             // Violates rule: DisposableFieldsShouldBeDisposed.
             // Should call aFieldOfADisposableType.Dispose();
 
             disposed = true;
-             // Suppress finalization of this disposed instance.
-             if (disposing)
-             {
-                 GC.SuppressFinalize(this);
-             }
+            // Suppress finalization of this disposed instance.
+            if (disposing)
+            {
+                GC.SuppressFinalize(this);
+            }
          }
       }