Built-in types table (C# Reference)

The following table shows the keywords for built-in C# types, which are aliases of predefined types in the System namespace.

C# type .NET type
bool System.Boolean
byte System.Byte
sbyte System.SByte
char System.Char
decimal System.Decimal
double System.Double
float System.Single
int System.Int32
uint System.UInt32
long System.Int64
ulong System.UInt64
object System.Object
short System.Int16
ushort System.UInt16
string System.String

Remarks

All of the types in the table, except object and string, are referred to as simple types.

The C# type keywords and their aliases are interchangeable. For example, you can declare an integer variable by using either of the following declarations:

int x = 123;
System.Int32 y = 123;

Use the typeof operator to get the System.Type instance that represents the specified type:

Type stringType = typeof(string);
Console.WriteLine(stringType.FullName);

Type doubleType = typeof(System.Double);
Console.WriteLine(doubleType.FullName);

// Output:
// System.String
// System.Double

See also