C# - Save object to JSON file
<p>I'm writing a Windows Phone Silverlight app. I want to save an object to a JSON file. I've written the following piece of code.</p>

<pre><code>string jsonFile = JsonConvert.SerializeObject(usr);
IsolatedStorageFile isoStore = IsolatedStorageFile.GetUserStoreForApplication();
IsolatedStorageFileStream isoStream = new IsolatedStorageFileStream("users.json", FileMode.Create, isoStore);

StreamWriter str = new StreamWriter(isoStream);
str.Write(jsonFile);
</code></pre>

<p>This is enough to create a JSON file but it is empty. Am I doing something wrong? Wasn't this supposed to write the object to the file?</p>