Type conversion is converting one type of data to another type. It is also known as Type Casting. In C#, type casting has two forms −
  • Implicit type conversion − These conversions are performed by C# in a type-safe manner. For example, are conversions from smaller to larger integral types and conversions from derived classes to base classes.
  • Explicit type conversion − These conversions are done explicitly by users using the pre-defined functions. Explicit conversions require a cast operator.
The following example shows an explicit type conversion − 
using System;

namespace TypeConversionApplication {
   class ExplicitConversion {
      static void Main(string[] args) {
         double d = 5673.74; 
         int i;
         
         // cast double to int.
         i = (int)d;
         Console.WriteLine(i);
         Console.ReadKey();
      }
   }
}
When the above code is compiled and executed, it produces the following result − 
5673

C# Type Conversion Methods

C# provides the following built-in type conversion methods −
Sr.No. Methods & Description
1 ToBoolean Converts a type to a Boolean value, where possible.
2 ToByte Converts a type to a byte.
3 ToChar Converts a type to a single Unicode character, where possible.
4 ToDateTime Converts a type (integer or string type) to date-time structures.
5 ToDecimal Converts a floating point or integer type to a decimal type.
6 ToDouble Converts a type to a double type.
7 ToInt16 Converts a type to a 16-bit integer.
8 ToInt32 Converts a type to a 32-bit integer.
9 ToInt64 Converts a type to a 64-bit integer.
10 ToSbyte Converts a type to a signed byte type.
11 ToSingle Converts a type to a small floating point number.
12 ToString Converts a type to a string.
13 ToType Converts a type to a specified type.
14 ToUInt16 Converts a type to an unsigned int type.
15 ToUInt32 Converts a type to an unsigned long type.
16 ToUInt64 Converts a type to an unsigned big integer.
The following example converts various value types to string type − 
using System;

namespace TypeConversionApplication {
   class StringConversion {
      static void Main(string[] args) {
         int i = 75;
         float f = 53.005f;
         double d = 2345.7652;
         bool b = true;

         Console.WriteLine(i.ToString());
         Console.WriteLine(f.ToString());
         Console.WriteLine(d.ToString());
         Console.WriteLine(b.ToString());
         Console.ReadKey();
            
      }
   }
}
When the above code is compiled and executed, it produces the following result − 
75
53.005
2345.7652
True