Python 3.x : move to next line

Question

I've got a small script that is extracting some text from a .html file.

f = open(local_file,"r")
for line in f:
    searchphrase = '<span class="position'
    if searchphrase in line:
        print("found it\n")

That works fine for me(error handling will be imported later), my problem is that the text I want to extract follows 2 lines after the searchphrase. How can I move 2 lines down in the .html file ?

Answer 1

You can advance f (which is an iterable) by two lines by calling next() on it twice:

with open(local_file,"r") as f
    for line in f:
        searchphrase = '<span class="position'
        if searchphrase in line:
            print("found it\n")
            next(f) # skip 1 line
            return next(f)  # and return the line after that.

However , if you are trying to parse HTML, consider using a HTML parser instead . Use BeautifulSoup , for example.

Answer 2

This works nice for me:

f = open(local_file,"r")
found = -1
for line in f:
    if found == 2:
        print("Line: "+line);
        break
    elif found > 0:
        found += 1
    else:
        searchphrase = '<span class="position'
        if searchphrase in line:
            print("found it")
            found = 1

The input file was:

bla
<span class="position">Hello</span>
blub
that's it
whatever

And the output of the program:

found it
Line: that's it

Instead of calling break you may also reset found to -1 to search for more occurences of the pattern...