Error message when you serialize a class by using the XMLSerializer class: "System.InvalidOperationException"

The System.InvalidOperationException error message is used to indicate that a method was not invoked for reasons other than invalid arguments. The System.InvalidOperationException error for the XmlSerializer class Serialize method is caused when you try to serialize a class that does not have a default constructor or a public modifier.

An instance of the class is created when the class is deserialized with the XmlSerializer.Deserialize method. The default constructor that is provided by the class is invoked by the Deserialize method to create the instance. Even if additional constructors are defined for the class, only the default constructor is invoked.

Steps to Reproduce the Behavior

1. Start Microsoft Visual Studio .NET or Microsoft Visual Studio 2005
2. Click Visual C# Projects under
   Project Types, and then click Console Application under Templates.
   
   Note In Visual Studio 2005, click Visual C# under Project Types.
3. In the generated default Class1.cs, replace the existing code with the following code:

   using System;
   using System.Xml;
   using System.Xml.Serialization;
   using System.Runtime.Serialization;
   using System.IO;
    
   
   namespace ConsoleTester
   {
   [Serializable]
   public class SerializerTest
   {
   public SerializerTest(string data)
   {
   this.data = data;
   }
   
   public string data;
   
   }
   
   class ConsoleMain
   {
   [STAThread]
   static void Main(string[] args)
   {
   SerializerTest testInstance = new SerializerTest("Hello World!");
   
   XmlSerializer ser = new XmlSerializer(typeof(SerializerTest));
   
   TextWriter writer = new StreamWriter("C:\\test.xml");
   ser.Serialize(writer, testInstance);
   writer.Close();
   
   }
   }
   
   }
   

   Note In Visual Studio 2005, replace the existing code in the Program.cs file.
4. Compile, and then run the code.

You receive the error message that is mentioned in the "Symptoms" section of this article.