urif
asked on
saving text from a file into memory
Hello all,
I have a console application that needs to read a file, get the text inside and save it into a memory stream or something the like, i need this because i will passing that text to a function and later i will show the resulting text on the screen. So this is what i need:
1. read from file.txt
2. fill a buffer with that text
3. pass the buffer to a function (this function will reverse the text)
4. show the resulting text on the screen.
any ideas how to build such a buffer?
thanx!
I have a console application that needs to read a file, get the text inside and save it into a memory stream or something the like, i need this because i will passing that text to a function and later i will show the resulting text on the screen. So this is what i need:
1. read from file.txt
2. fill a buffer with that text
3. pass the buffer to a function (this function will reverse the text)
4. show the resulting text on the screen.
any ideas how to build such a buffer?
thanx!
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hi madshi ;-)
hi meikl... (-:
ASKER
To Madshi:
Thx, are you sure the file text will fit into a normal string?
furthermore, where do you return that string?
Thx, are you sure the file text will fit into a normal string?
furthermore, where do you return that string?
urif, since Delphi 2, Strings can be any size up to about 2GB. So if your text file is larger, well... hm... ;-)
To reverse a string, you could use this code:
procedure SwapChar(var Data; Count: Integer);
var
B,E: ^Byte;
Temp: Byte;
begin
if Count>1 then begin
E:=@Data;
B:=E;
Inc(E,Count-1);
Count:=Count shr 1;
while Count>0 do begin
Temp:=B^;
B^:=E^;
E^:=Temp;
Inc(B);
Dec(E);
Dec(Count);
end;
end;
end;
and then after loading the text into YourString using Madshi's code:
SwapChar(YourString[1],Len
Easy, isn't it...
To reverse a string, you could use this code:
procedure SwapChar(var Data; Count: Integer);
var
B,E: ^Byte;
Temp: Byte;
begin
if Count>1 then begin
E:=@Data;
B:=E;
Inc(E,Count-1);
Count:=Count shr 1;
while Count>0 do begin
Temp:=B^;
B^:=E^;
E^:=Temp;
Inc(B);
Dec(E);
Dec(Count);
end;
end;
end;
and then after loading the text into YourString using Madshi's code:
SwapChar(YourString[1],Len
Easy, isn't it...
ASKER
sorry about my naivity, i'm a c programmer (in linux/unix!!!) i'm new to this windows, my pascal is the pascal learned in college
thx for your help, i really apreciated!
thx for your help, i really apreciated!
>> Thx, are you sure the file text will fit into a normal string?
As AvonWyss already pointed out, a string can theoretically hold up to 2 GB data. But there is a limit, namely the available RAM + swap file. Generally you can easily load text files up to 1 MB into memory, if the text files are much larger, you should think about loading it in in thunks.
>> furthermore, where do you return that string?
It works like this:
var strVar : string;
begin
if LoadStrFromFile('c:\autoex
// here you have the file in the "strVar"
end else
ShowMessage('loading failed...');
>> sorry about my naivity, i'm a c programmer
No problem... (-:
Regards, Madshi.
As AvonWyss already pointed out, a string can theoretically hold up to 2 GB data. But there is a limit, namely the available RAM + swap file. Generally you can easily load text files up to 1 MB into memory, if the text files are much larger, you should think about loading it in in thunks.
>> furthermore, where do you return that string?
It works like this:
var strVar : string;
begin
if LoadStrFromFile('c:\autoex
// here you have the file in the "strVar"
end else
ShowMessage('loading failed...');
>> sorry about my naivity, i'm a c programmer
No problem... (-:
Regards, Madshi.
ASKER
thx again
it provides a loadfromfile-method,
a pointer and a size proberty
or you can even use a string
loading your text in a tsringlist and forward its text-proeprty