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why i cant write records into file in turbo-pascal???
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hi,
whenever i try to write records into the file, only the first piece of records can be written. even some simple program like the following cant work properly.
when i open 'infile.txt', only 'name' is shown but not 'name ' and 'second'. however, turbo-pascal works perfectly when array is written back into text file.
in this program, both 'name' and 'second' are shown. i am using both turbo-pascal and dev-pascal. is it the problem of my problem or the pascal software?????
thx for help!!!
grace
whenever i try to write records into the file, only the first piece of records can be written. even some simple program like the following cant work properly.
type thing=record
name:string;
end;
var f:file of thing;
data:array [1..2] of thing;
i:integer;
begin
assign(f, 'infile.txt');
rewrite(f);
data[1].name:='name';
data[2].name:='second';
for i:= 1 to 2 do
write(f, data[i]);
close(f);
end.when i open 'infile.txt', only 'name' is shown but not 'name ' and 'second'. however, turbo-pascal works perfectly when array is written back into text file.
var f:text;
data:array [ 1..2 ] of string;
i:integer;
begin
assign(f, 'infile.txt');
rewrite(f);
data[1]:='name';
data[2]:='second';
for i:=1 to 2 do
writeln(f, data[i]);
close(f);
end.in this program, both 'name' and 'second' are shown. i am using both turbo-pascal and dev-pascal. is it the problem of my problem or the pascal software?????
thx for help!!!
grace
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Join Date: Feb 2009
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your first program working properly!I run your code and it is worked perfectly....(of course mine is Turbo Pascal 7.0 and dev pascal 1.9.2)listen your code:
pascal Syntax (Toggle Plain Text)
Be a good part of the community.Don't be ungrateful.
If you ask something on the forum and you got the right answer then mark as solved!
If my opinion helped to you a lot then sometimes give reputation point to me.
I'm just a pascal programmer from Hungary.
Farewell...
If you ask something on the forum and you got the right answer then mark as solved!
If my opinion helped to you a lot then sometimes give reputation point to me.
I'm just a pascal programmer from Hungary.
Farewell...
•
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Join Date: Feb 2009
Posts: 443
Reputation:
Solved Threads: 106
Posting Pro in Training
I'm programming under windows xp
Last edited by FlamingClaw; Aug 19th, 2009 at 4:26 am.
Be a good part of the community.Don't be ungrateful.
If you ask something on the forum and you got the right answer then mark as solved!
If my opinion helped to you a lot then sometimes give reputation point to me.
I'm just a pascal programmer from Hungary.
Farewell...
If you ask something on the forum and you got the right answer then mark as solved!
If my opinion helped to you a lot then sometimes give reputation point to me.
I'm just a pascal programmer from Hungary.
Farewell...
It is because you have misunderstood something.
A string is not a simple POD type -- it is an object type -- which you cannot write directly to file (according to Delphi standards [and also ISO standards, but that's beside the point
]).
The write[ln] functions know how to transform a string into a simple sequence of characters.
They do not know how to handle your thing type, because it has a non-POD member (the string).
When you create file types, they must be sequences of non-object types. Hence,
succeeds.
What you can do is write procedures/methods that know how to write your non-POD type to a given file, then call it when you wish to write it.
For more information, google around "delphi or pascal object serialization".
Hope this helps.
A string is not a simple POD type -- it is an object type -- which you cannot write directly to file (according to Delphi standards [and also ISO standards, but that's beside the point
]).The write[ln] functions know how to transform a string into a simple sequence of characters.
They do not know how to handle your thing type, because it has a non-POD member (the string).
When you create file types, they must be sequences of non-object types. Hence,
type tFooFile: file of string; fails, where Pascal Syntax (Toggle Plain Text)
What you can do is write procedures/methods that know how to write your non-POD type to a given file, then call it when you wish to write it.
For more information, google around "delphi or pascal object serialization".
Hope this helps.
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