C# Language Specification

Implicit conversions

The following conversions are classified as implicit conversions:

• 
  Identity conversions
  
• 
  Implicit numeric conversions
  
• 
  Implicit enumeration conversions.
  
• 
  Implicit nullable conversions
  
• 
  Null literal conversions
  
• 
  Implicit reference conversions
  
• 
  Boxing conversions
  
• 
  Implicit dynamic conversions
  
• 
  Implicit constant expression conversions
  
• 
  User-defined implicit conversions
  
• 
  Anonymous function conversions
  
• 
  Method group conversions
  

Implicit conversions can occur in a variety of situations, including function member invocations (§7.5.4), cast expressions (§7.7.6), and assignments (§7.17).

The pre-defined implicit conversions always succeed and never cause exceptions to be thrown. Properly designed user-defined implicit conversions should exhibit these characteristics as well.

For the purposes of conversion, the types object and dynamic are considered equivalent.

However, dynamic conversions (§6.1.8 and §6.2.6) apply only to expressions of type dynamic (§4.7).

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