Multi line file handling

[Prashant Thorat]

Hi All,

I have a file with multiple lines ,I want to assign all content to variable
& then want to work on it.
Like want to match pattern /window/ from it.
how can it is possible ?
for example -

open ( F1 ,"file.txt") || die "$!";

$a=<F1>;

if (/window/i){print
"it is present\n";
}