[Overview][Constants][Types][Classes][Procedures and functions][Variables] Reference for unit 'System' (#rtl)

Val

Calculate numerical value of a string.

Declaration

Source position: system.fpd line 49

procedure Val(

  const S: String;

  var V;

  var Code: Word

);

Description

Valconverts the value represented in the string Sto a numerical value, and stores this value in the variable V, which can be of type Longint, Realand Byte. If the conversion isn't succesfull, then the parameter Codecontains the index of the character in Swhich prevented the conversion. The string Sis allowed to contain spaces in the beginning. The string Scan contain a number in decimal, hexadecimal, binary or octal format, as described in the language reference.

Errors

If the conversion doesn't succeed, the value of Codeindicates the position where the conversion went wrong.

See also

Str

  

Convert a numerical value to a string.

Example

Program Example74;

{ Program to demonstrate the Val function. }
Var I, Code : Integer;

begin
  Val (ParamStr (1),I,Code);
  If Code<>0 then
    Writeln ('Error at position ',code,' : ',Paramstr(1)[Code])
  else
    Writeln ('Value : ',I);
end.