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### Author Topic: Put Strings together + doesn't work  (Read 312 times)

• Full Member
• Posts: 121
##### Put Strings together + doesn't work
« on: September 20, 2022, 10:27:40 am »
Is there another way, then to use concat to combine Strings?
+ doesn'T work here.
POS is always 0

Code: [Select]
`program RS232_find;Uses CRT;VAR key : Char;  RX : ARRAY [0..10] OF char;  position : BYTE;  kurzwort : string[13];Procedure keys;  Begin  key := readkey;    case key of    #72 :  writeln('up');    #80 :  writeln('down');    #75 :  writeln('left');    #77:   writeln('right');    end; // caseend;  // if #0//end;begin  RX[0] := chr(\$FF);  RX[1] := chr(\$FF);  RX[2] := chr(\$01);  RX[3] := chr(\$01);  RX[4] := chr(\$1B);  RX[5] := chr(\$52);  RX[6] := chr(\$00);  RX[7] := chr(\$52);  RX[8] := chr(\$30);  RX[9] := chr(\$01);  RX[10] := chr(\$01); kurzwort := chr(\$52)+ chr(\$00)+ chr(\$52);  While TRUE DO  Begin    position := Pos(kurzwort, rx);    Write(position);    keys;  end;end.        `
Wind XP / 7 / 10

#### marcov

• Hero Member
• Posts: 10399
• FPC developer.
##### Re: Put Strings together + doesn't work
« Reply #1 on: September 20, 2022, 10:44:57 am »
That's because RX is not a string but an array of char. Probably it gets a conversion to pchar, and pchar's stop at \$00

• Full Member
• Posts: 121
##### Re: Put Strings together + doesn't work
« Reply #2 on: September 20, 2022, 10:59:09 am »
oh, ok.
I thought String of Char and String are the same:-(
Wind XP / 7 / 10

#### Zvoni

• Hero Member
• Posts: 1534
##### Re: Put Strings together + doesn't work
« Reply #3 on: September 20, 2022, 12:24:02 pm »
oh, ok.
I thought String of Char and String are the same:-(
How do you figure that? Besides the fact that String is a managed type, and Array of char or pchar is more or less ANSI only
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#### Arioch

• Sr. Member
• Posts: 414
##### Re: Put Strings together + doesn't work
« Reply #4 on: September 26, 2022, 07:07:50 pm »
oh, ok.
I thought String of Char and String are the same:-(
How do you figure that? Besides the fact that String is a managed type, and Array of char or pchar is more or less ANSI only

Well, original Pascal did not have strings (except for string literals), so school books written on top of J&W report used to call char arrays as strings, for having nothing better.

TurboPascal strings vs C strings were once a matter of hot internet debates, so everyone knew specifics, but probably no more.