Lesson 4: Converting bet. types.

Conversion in C#

• narrowing conversion - prohibited.
• widening conversion - allowed.

Ways to Perform Explicit Conversion

• System.Convert - bet. types that impl. IConvertible interface.
• (type) - cast operator - bet. types that define conversion operators.

Boxing/Unboxing

• boxing - converts a value type to ref type. (e.g. convert int -> Object)
• unboxing - ref -> value.
• boxing/unboxing - incur overheads.
• boxing - occurs on calling virtual mthds that structure inherits from System.Object - e.g. ToString().
• Best Practices:
  1. Impl. overloads for mthds that accept mult. value types. Better to create mult. overloads than 1 proc taking Object.
• 2. Use generics instead of accpeting Object args.
• 3. Override ToString, Equals, GetHash virtual members when defining structures.

How to Implement Conversion in Custom Types

• conversion operators - for narrowing ( k'word explicit)/widening (k'word implicit) conversions bet. numeric types.
• Override ToString() to provide conversion to strings, and override Parse() to provide conversion from strings.