title: Is this extension method thread safe?
body: <p>I have created extension methods to map between objects but I am worried it may not be thread safe. Here is the method:</p>
  <pre><code>public static SavableRecord ToSavableRecordForMongoDB(this Record record)
  {
      SavableRecord savableRecord = new SavableRecord();
  
      if (record.Fields == null)
          throw new ArgumentException(&quot;Fields of record cannot be null&quot;);
  
      if (string.IsNullOrWhiteSpace(record.id))
          savableRecord._id = record.id;
  
      foreach (KeyValuePair&lt;string, Field&gt; item in record.Fields)
          savableRecord.Fields[item.Key] = new Field(item.Value);
  
      return savableRecord;
  }
  </code></pre>
  <p>If this method is not thread safe what can I do to make it thread safe.</p>
  <h2>Update</h2>
  <p>The <code>record</code> object is passed in the controller in an MVC project. The <code>record</code> object is never changed while in this controller or its path.</p>