HN>How do you convert a string[1] to a char?

HN>hne...@ac.net

{--------------------------------------}
program Sample;
var
   S: string;
   C: char;

begin
   S := 'Any old string you want';
   C := S[1];
end.
{--------------------------------------}

THEN:
    c := s[1];

Of course if s is empty c is unknown, so the following is safer, but only in
that when s is empty c will have a defined value.

    s := s + #0;
    c := s[1];

Let's say you have the declarations:

Var MyStr  : String[1];
    MyChar : Char;

You could as easily assign your string to a char by an instruction like this:

  MyChar := MyStr[1];

Remember that a string is simply an array of characters, so referencing an
element is equivalent to accessing a single char.

You just have to consider here that there really is a character in your string.
If the string is empty (MyStr = ''), then the character you get from MyStr[1] is
garbage.  (It is usually the last character used in the string but this may be
implementation dependent)

So, when converting, it is better to have...

  If (Length(MyStr) = 0) then <Error>
    else MyChar := MyStr[1];

<clifp...@airmail.net>    3:50PM  3/21/96

The output produced by this program is:

No Crash!   Ch = Z   OneStr = A
Ch = C   OneStr = C
Ch = B   OneStr = B

<<<<Just Press Enter >>>>

---------------------------------------------------------------

Program StrToChar;

CONST  TestChar = 'Z';
       TestStr = 'ABC';

VAR
OneStr:String[1];
Ch:Char;
ThreeStr:String[3];

Begin
Writeln;

Ch := TestChar;
OneStr := TestStr;
Writeln('No Crash!  Ch = ', Ch, '   OneStr = ', OneStr);

OneStr := Copy(TestStr, 3, 1);
Ch := OneStr[1];          (* This works either way, note below *)
Writeln('Ch = ', Ch, '   OneStr = ', OneStr);

ThreeStr := TestStr;
Ch := ThreeStr[2];     (* Ch := TestStr[2] will fail *)
OneStr[1] := Ch;       (* Reverse of above *)
Writeln('Ch = ', Ch, '   OneStr = ', OneStr);

The *type* may be string[1], but the expression my_str[1] evaluates to a char