Object.ToString Method

ToString is the major formatting method in the .NET Framework. It converts an object to its string representation so that it is suitable for display. (For information about formatting support in the .NET Framework, see Formatting Types.)

The default implementation of the ToString method returns the fully qualified name of the type of the Object, as the following example shows.

using System;

public class Example
{
   public static void Main()
   {
      Object obj = new Object();
      Console.WriteLine(obj.ToString());
   }
}
// The example displays the following output:
//      System.Object

Because Object is the base class of all reference types in the .NET Framework, this behavior is inherited by reference types that do not override the ToString method. The following example illustrates this. It defines a class named Object1 that accepts the default implementation of all Object members. Its ToString method returns the object's fully qualified type name.

using System;
using Examples;

namespace Examples
{
   public class Object1
   {
   }
}

public class Example
{
   public static void Main()
   {
      object obj1 = new Object1();
      Console.WriteLine(obj1.ToString());
   }
}
// The example displays the following output:
//   Examples.Object1

Types commonly override the ToString method to return a string that represents the object instance. For example, the base types such as Char, Int32, and String provide ToString implementations that return the string form of the value that the object represents. The following example defines a class, Object2, that overrides the ToString method to return the type name along with its value.

using System;

public class Object2
{
   private object value;

   public Object2(object value)
   {
      this.value = value;
   }

   public override string ToString()
   {
      return base.ToString() + ": " + value.ToString();
   }
}

public class Example
{
   public static void Main()
   {
      Object2 obj2 = new Object2('a');
      Console.WriteLine(obj2.ToString());
   }
}
// The example displays the following output:
//       Object2: a

When you implement your own types, you should override the ToString method to return values that are meaningful for those types. Derived classes that require more control over formatting than ToString provides can implement the IFormattable interface. Its IFormattable.ToString(String, IFormatProvider) method enables you to define format strings that control formatting and to use an IFormatProvider object that can provide for culture-specific formatting.

.NET Framework

.NET Framework Client Profile

Portable Class Library

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

Reference

Other Resources