Difference Between string and String in C#.NET

There is no different between string and String (System.String). string is an alias for System.String in C#.Net.

They compile to the same code, so no difference at execution time. The complete list of aliases in C#.Net is

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

See Also