How do i shrink the length of a string variable ?

[pascalbythree]

How do i shrink the length of a string variable ?

PortStr : String[3]

Does not seem to work, somebody how to go for a string of 3 characters?

[rvk]

What does not work?

String[3] is a shortstring type (old dos/turbo pascal type).
You define the length there and you can't change it.

If you want a dynamic string you just use String.
You can change the length then with Setlength.

What exactly do you want and how are you going to use it?

[KodeZwerg]

array[0..2] of char / ansichar / widechar ?

[rvk]

Code: Pascal  [Select][+][-]

1. var
2.   PortStr: String;
3. begin
4.   PortStr := '123';

Is also a string of 3 characters.
So it's just a question of what's going wrong and what it is used for.

You don't need to shrink a string because it's dynamic length in nature.

[Zvoni]

Code: Pascal  [Select][+][-]

1. program Project1;
2. Var
3.   s:String;
4. begin
5.   s:='ABCDEFGH';
6.   Writeln(s);
7.   SetLength(s,5);
8.   Writeln(s);
9. end.

Returns
ABCDEFGH
ABCDE

[Чебурашка]

How do i shrink the length of a string variable ?

Could you explain better what you need, possibly with an example?

[pascalbythree]

Code: Pascal  [Select][+][-]

1. function IntToStr(i:Longint):String;
2. var S : String;
3. begin
4.  Str(i,S);
5.  result:=S;
6. end;

Further, does anybody know how to go from StrToInt ? The otherway around as above ?

[rvk]

Code: Pascal  [Select][+][-]

1. function IntToStr(i:Longint):String;
2. var S : String;
3. begin
4.  Str(i,S);
5.  result:=S;
6. end;

So, what exactly is your problem now?
I'm not sure what this bit of code has to do with your question 

BTW. Depending on your mode you could also just do i.toString.
No need for IntToStr() function. There are a lot more helper options.

Further, does anybody know how to go from StrToInt ? The otherway around as above ?

IntToStr() or IntToStrDef() or TryStrToInt().

[Чебурашка]

Further, does anybody know how to go from StrToInt ? The otherway around as above ?

Please explain better whet you need.

[KodeZwerg]

Further, does anybody know how to go from StrToInt ? The otherway around as above ?

Perhaps by using "Uses SysUtils" and call IntToStr() or StrToInt() and not any selfmade stuff.

[Zvoni]

Further, does anybody know how to go from StrToInt ? The otherway around as above ?

Perhaps by using "Uses SysUtils" and call IntToStr() or StrToInt() and not any selfmade stuff.

Yepp. SysUtils to get the typeHelpers

SomeInteger.ToString;
SomeString.ToInteger;

[pascalbythree]

On a AVR ? Or is the example above for ARM?

[TRon]

On a AVR ? Or is the example above for ARM?

The example is for Free Pascal (unit sysutils in particular as that includes the helpers) . But in case you are memory restricted then using sysutils is not the smartest idea because of its size.

[KodeZwerg]

Without SysUtils in a very size saving way

Code: Pascal  [Select][+][-]

1. function IntToStr(const i: Integer): string;
2. begin
3.  Str(i, Result);
4. end;
5.  
6. function StrToInt(const s: string): Integer;
7. var
8.  code: Integer;
9. begin
10.  Val(s, Result, code);
11. end;

Beware, none of this has any kind of checking ... for that you can try those:

Code: Pascal  [Select][+][-]

1. function StrToIntDef(const s: string; const i: Integer): Integer;
2. var
3.  code: Integer;
4. begin
5.  Val(s, Result, code);
6.   if(code <> 0) then
7.     Result := i;
8. end;
9.  
10. function TryStrToInt(const s: string; out i: Integer): Boolean;
11. var
12.  code, ii : integer;
13. begin
14.   Result := False;
15.   ii := 0;
16.   Val(s, ii, code);
17.   if (code = 0) then
18.     begin
19.       i := ii;
20.       Result := True;
21.      end;
22. end;

[paweld]

@KodeZwerg: as @rvk wrote such functions already exist, what is the purpose of duplicating them?