How to Handle CA2202 Warnings When Disposing Multiple Objects in C#?

Addressing CA2202 Warnings When Disposing Multiple Objects in C#

The following C# code example generates CA2202 warnings in Visual Studio Code Analysis for CryptoStream and MemoryStream due to potential repeated Dispose calls. Instead of code modification, suppressing these warnings is the recommended approach.

Suppressing CA2202 Warnings: The Preferred Solution

Given the consistent object disposal pattern in the code, suppressing the warnings is preferable to altering the code. The concern of multiple Dispose calls is unfounded as the IDisposable.Dispose method is designed to be idempotent (ignoring subsequent calls after the first). The using statement handles this elegantly.

Here's how to suppress the warnings:

<code class="language-csharp">[System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Usage", "CA2202:Do not dispose objects multiple times")]
public static byte[] Encrypt(string data, byte[] key, byte[] iv) {
  using (var memoryStream = new MemoryStream()) {
    using (var cryptograph = new DESCryptoServiceProvider())
    using (var cryptoStream = new CryptoStream(memoryStream, cryptograph.CreateEncryptor(key, iv), CryptoStreamMode.Write))
    using (var streamWriter = new StreamWriter(cryptoStream)) {
      streamWriter.Write(data);
    }
    return memoryStream.ToArray();
  }
}</code>

Rationale for Suppression

The IDisposable.Dispose method documentation explicitly states that calls beyond the first are ignored. The nested using statements in the code create a scenario where multiple objects manage disposal, yet this is handled correctly by the framework. Therefore, the CA2202 warning is unnecessary and can be safely suppressed.

The above is the detailed content of How to Handle CA2202 Warnings When Disposing Multiple Objects in C#?. For more information, please follow other related articles on the PHP Chinese website!