Data Conversion

Integers, floating point numbers, and strings can represent the same values, but use different methods to store them in memory. Sometimes, simple assignment will instruct the compiler to make the necessary conversion (such as assigning an integer to a floating point variable). However, particularly when using variants, dates, or strings, you may want explicit control.

If you want to treat a memory location as another data type without converting it, then see casting.

See String Functions for additional functions to convert to and from strings.

Visual Basic | Delphi

Visual Basic 6.0

The following functions will convert either a string or an expression to the indicated types. If the expression is outside the result type range, then an error results.

CBool	Boolean	CByte	Byte (0 to 255)
CCur	Currency	Cdate	Date
CDbl	Double (Floating point)	CDec	Decimal (weird)
CInt	Integer (16 bits)	CLng	Long (32-bit Integer)
CSng	Single (Floating point)	CStr	String
Cvar	Variant	Format	String
Int	Integer part of number	Asc	Byte (0 to 255)
Fix	Integer part of number	Val	Numeric
Hex	String	Str	String
Oct	String

val, CSng, and CDbl will convert strings to floating point (real) numbers. However, val assumes that the period (.) is the only possible decimal separator, and the other two recognize international decimal and thousands separators, depending on the system's settings.

Delphi

Use ord to convert an enumerated variable to anything else.

type
  Txx = (txRed, txBlue, txGreen);

var
  xx : Txx    ;
  i  : integer;

begin

  xx := txRed       ;
  i  := ord(xx)     ; // converts a variable
  i  := ord(txGreen);
  i  := ord('s')    ; // also works for characters

Converting real (floating point) numbers to integers (for a complete list, see "Arithmetic routines")

i := Trunc(x); // Always rounds towards zero
i := Int(x)  ; // Always rounds towards zero
i := Round(x); // Rounds to the nearest integer
i := Frac(x) ; // Returns the fractional part

i := Ceil(x) ; // Rounds up
i := Floor(x); // Rounds down

Author: Robert Clemenzi - clemenzi@cpcug.org

Data Conversion

Visual Basic 6.0

Delphi

URL: http:// cpcug.org / user / clemenzi / technical / Languages / DataConversion.htm