Type.GetType("System.Integer") returns null value (Nothing)


VB in it’s classic state (pre .Net) had an Integer data type. So, in VB.Net you can still use Integer in the syntax (Dim x As Integer) but it will be using a System.Int32. Now, if you try to do a Type.GetType(“System.Integer”) it will return a null value whereas Type.GetType(“System.Int32”) will correctly return a type initialized to Int32. If you’re dynamically creating types then using the GetType to the appropriate CLR type is a must. Here are two links, one for .Net 3.5 and one for .Net 4.0 showing the data types.

  1. http://msdn.microsoft.com/en-us/library/47zceaw7(v=VS.90).aspx
  2. http://msdn.microsoft.com/en-us/library/47zceaw7(v=VS.100).aspx

For posterity, here is the table reference in case the above links stop working:

| Visual Basic type | Common language runtime type structure | Nominal storage allocation | Value range | | ----------------- | -------------------------------------- | -------------------------- | ----------- | | Boolean | Boolean | Depends on implementing platform | True or False | | Byte | Byte | 1 byte | 0 through 255 (unsigned) | | Char (single character) | Char | 2 bytes | 0 through 65535 (unsigned) | | Date | DateTime | 8 bytes | 0:00:00 (midnight) on January 1, 0001 through 11:59:59 PM on December 31, 9999 | | Decimal | Decimal | 16 bytes | 0 through +/-79,228,162,514,264,337,593,543,950,335 (+/-7.9...E+28) † with no decimal point; 0 through +/-7.9228162514264337593543950335 with 28 places to the right of the decimal;

smallest nonzero number is +/-0.0000000000000000000000000001 (+/-1E-28) † | | Double (double-precision floating-point) | Double | 8 bytes | -1.79769313486231570E+308 through -4.94065645841246544E-324 † for negative values;

4.94065645841246544E-324 through 1.79769313486231570E+308 † for positive values
| | Integer | Int32 | 4 bytes | -2,147,483,648 through 2,147,483,647 (signed) | | Long (long integer) | Int64 | 8 bytes | -9,223,372,036,854,775,808 through 9,223,372,036,854,775,807 (9.2...E+18 †) (signed) | | Object | Object (class) | 4 bytes on 32-bit platform

8 bytes on 64-bit platform
| Any type can be stored in a variable of type Object | | SByte | SByte | 1 byte | -128 through 127 (signed) | | Short (short integer) | Int16 | 2 bytes | -32,768 through 32,767 (signed) | | Single (single-precision floating-point) | Single | 4 bytes | -3.4028235E+38 through -1.401298E-45 † for negative values;

1.401298E-45 through 3.4028235E+38 † for positive values
| | String (variable-length) | String (class) | Depends on implementing platform | 0 to approximately 2 billion Unicode characters | | UInteger | UInt32 | 4 bytes | 0 through 4,294,967,295 (unsigned) | | ULong | UInt64 | 8 bytes | 0 through 18,446,744,073,709,551,615 (1.8...E+19 †) (unsigned) | | User-Defined (structure) | (inherits from ValueType) | Depends on implementing platform | Each member of the structure has a range determined by its data type and independent of the ranges of the other members | | UShort | UInt16 | 2 bytes | 0 through 65,535 (unsigned) |