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Microsoft => Microsoft DOS => Topic started by: Teroro on October 27, 2021, 03:44:35 AM

Title: Create strings using echo commands
Post by: Teroro on October 27, 2021, 03:44:35 AM

So, I started messing around with a .bat file and started learning how to use variables, user input, show text using the commands: echo,set,etc.
And I noticed I can create files with the command: echo > (File name) Which was really intresting but I ran into a problem.
When creating a file you can do: echo "Text in it" > (File name) and I tried putting a CPP script in it but it doesn't seem to work. Can anyone tell me why?

I tried putting it into a string:

Code: [Select]

set Code=#include<fstream>usingnamespacestd;ifstreamfin("");ofstreamfout("");int main(){inta,b;fin>>a>>b;fout<<a*b;I tried directly applying it:

Code: [Select]

echo #include<fstream>usingnamespacestd;ifstreamfin("");ofstreamfout("");int main(){inta,b;fin>>a>>b;fout<<a*b; > "%CPPFileName%"
Can anyone help me with this?
Heres the full code:

Code: [Select]

@echo off
echo In File name:
set /p File1Name=
echo 2 Variables:
set /p Variables=
echo %Variables% > "%File1Name%"
echo Out File name:
set /p File2Name=
echo 0 > "%File2Name%"
echo CPP File name:
set /p CPPFileName=
set Code=#include<fstream>usingnamespacestd;ifstreamfin("");ofstreamfout("");int main(){inta,b;fin>>a>>b;fout<<a*b;
echo #include<fstream>usingnamespacestd;ifstreamfin("");ofstreamfout("");int main(){inta,b;fin>>a>>b;fout<<a*b; > "%CPPFileName%"


Title: Re: Create strings using echo commands
Post by: Squashman on October 27, 2021, 03:47:04 PM

The obvious culprit should be the >.  This character is a special character to tell the script to redirect the output to the file. Otherwise known as Standard Output.  The < is also a special character as it is used for Standard Input.  Any special character that you need to use Literally, needs to be escaped by the ^ character.
example

Code: [Select]

echo #include^<fstream^>usingnamespacestd;ifstreamfin(""); >"%CPPFileName%"

Title: Re: Create strings using echo commands
Post by: Teroro on October 28, 2021, 01:41:49 PM

I tried but it still doesn't create my file...

Code: [Select]

@echo off
echo In File name:
set /p File1Name=
echo 2 Variables:
set /p Variables=
echo %Variables% > "%File1Name%"
echo Out File name:
set /p File2Name=
echo 0 > "%File2Name%"
echo CPP File name:
set /p CPPFileName=
echo #include^<fstream^>usingnamespacestd;ifstreamfin("%File1Name%");ofstreamfout("%File2Name%");int main(){inta,b;fin>>a>>b;fout<<a*b;} > "%CPPFileName%"


Title: Re: Create strings using echo commands
Post by: Teroro on October 28, 2021, 01:47:26 PM

It worked omg.
Thank you very much!