Val
procedure
Converts a
string to a numeric representation.
Unit
System
Category
string handling routines
procedure Val(S;
var V;
var Code: Integer);
Description
Val converts the
string value S
to its numeric representation,
as if it were
read from a text
file with Read.
S
is a
string-
type expression; it must be a sequence
of characters that form a signed real number.
V
is an integer-
type or real-
type variable.
If V
is an integer-
type variable, S must form a whole number.
Code
is a variable
of type Integer.
If the
string is invalid, the
index of the offending character
is stored in Code; otherwise, Code
is set to zero.
For a null-terminated
string, the error position returned
in Code
is one larger than the actual zero-based
index of the character
in error.
Val performs range checking differently depending upon the setting
of the $R compiler directive
and the
type of the parameter V.
Setting Result
{$R+} An
out-
of-range value always generates a
run-time error.
{$R-} The values
for out-
of-range vary depending upon the data
type of V.