Solved

question about chr

Posted on 1998-11-26
6
206 Views
Last Modified: 2010-04-04
I am using Delphi 3 and have 2 edit boxes on the screen and 1 button.

In 1 edit box, I type lower case alphabet only words.  When I press the button, I take each character 1 at a time, and add 1 to the ordinal value of the character.  (Up to this point, this works fine)

Then I want to store each 'new' character into a string variable with a statement like this:  var output:string;
                                          input:string;
                                          x:integer;
  x:=ord(input[i]);
  x:=x+1;
  output:=chr(x);  <-- this is the line that the compiler keeps on saying that there is an error.
What am I doing wrong?

Thanks

0
Comment
Question by:psabourin
  • 2
  • 2
  • 2
6 Comments
 
LVL 5

Accepted Solution

by:
scrapdog earned 50 total points
ID: 1348167
The problem is that you are trying to store a char in a string variable.  These are two different types.

One solution would be to use concatenation.

x:=ord(input[i]);
  x:=x+1;
  output := '';
  output := output + chr(x);  


Or you could set one of the chars in the string directly.

Like this:

x := ord(input[i]);
  SetLength(s,1);
  s[1] :=chr(x);


I don't know what exactly your purpose is, but I would suggest something like this:

output := '';
for i := 1 to length(input) do begin
  x:=ord(input[i]);
  x:=x+1; if x>255 then x := 0;
  output := output + chr(x);
end;

Output will be contain a string of characters, all 1 greater than the corresponding character in input.


0
 
LVL 5

Expert Comment

by:scrapdog
ID: 1348168
Or, even better, you could possibly do this:

output := '';
for i := 1 to length(input) do
  output := output + succ(input[i]);

where you can avoid changing to an integer altogether.
(succ is the successor function, an ANSI pascal function.  Check your help file on it for more details.)

0
 
LVL 27

Expert Comment

by:kretzschmar
ID: 1348169
hi psabourin,

your OutputVar is a string and you will place there a Char, thats incompatibel.

When the Output holds only a Char you can use

Output := '';
Output := Output + Chr(X);

When Output holds the InputString manipulated each Char Increased by one then
only

Output := Output + Chr(X);

To manipilulate the whole InputString to OutputString
Use

Output := '';
For I := 1 to Length(Input) do Output := Output + Chr(Ord(Input[I])+1);


Meikl

0
Free Tool: IP Lookup

Get more info about an IP address or domain name, such as organization, abuse contacts and geolocation.

One of a set of tools we are providing to everyone as a way of saying thank you for being a part of the community.

 

Author Comment

by:psabourin
ID: 1348170
Thanks
0
 
LVL 27

Expert Comment

by:kretzschmar
ID: 1348171
wow, this q was from nov '98
0
 

Author Comment

by:psabourin
ID: 1348172
Sorry, got tied up with other stuff.  I meant to do this a long time ago.  But better late than never, I suppose!
0

Featured Post

Free Tool: Site Down Detector

Helpful to verify reports of your own downtime, or to double check a downed website you are trying to access.

One of a set of tools we are providing to everyone as a way of saying thank you for being a part of the community.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Introduction The parallel port is a very commonly known port, it was widely used to connect a printer to the PC, if you look at the back of your computer, for those who don't have newer computers, there will be a port with 25 pins and a small print…
In this tutorial I will show you how to use the Windows Speech API in Delphi. I will only cover basic functions such as text to speech and controlling the speed of the speech. SAPI Installation First you need to install the SAPI type library, th…
Two types of users will appreciate AOMEI Backupper Pro: 1 - Those with PCIe drives (and haven't found cloning software that works on them). 2 - Those who want a fast clone of their boot drive (no re-boots needed) and it can clone your drive wh…

856 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question