StrToIntDef

function StrToIntDef(const IntegerString string; Default Integer):Integer;

The StrToIntDef function converts an Integer string, IntegerString such as '100' into an Integer value, with a Default if the conversion fails.

It supports +ve and -ve numbers, and hexadecimal numbers, as prefixed by $ or 0x.

Example:

var
  firstNumber,secondNumber, thirdNumber, fourthNumber : Integer;

begin

  firstNumber := 32;
  secondNumber := StrToIntDef('test00', 10);  // Leading blanks are ignored
  thirdNumber := StrToIntDef('$1E', 0);    // Hexadecimal values start with a '$'
  fourthNumber := StrToIntDef('-0x1E', 0);  // ... or with a '0x'

  ShowMessage('firstNumber : '+IntToStr(firstNumber));
  ShowMessage('secondNumber : '+IntToStr(secondNumber));
  ShowMessage('thirdNumber : '+IntToStr(thirdNumber));
  ShowMessage('fourthNumber : '+IntToStr(fourthNumber));

end;

Output:

firstNumber : 32
secondNumber : 10
thirdNumber : 30
fourthNumber : -30