有没有办法只在python中读取csv文件中的标题？

Question

I was wondering if there was a way to only read the header info from a csv file without loading the whole file. I'm dealing with large csv files and would rather not have to load the whole thing.

Thanks!

Answer 1

You wouldn't normally read the whole file anyway. Just create the CSV reader and call next() on it once.

import csv
f = open('myfile.csv')
reader = csv.reader(f)
header = reader.next()

Answer 2

with open(filename) as in_file:
    csv_reader = csv.reader(in_file)
    header = next(csv_reader)

This works because csv.reader() returns a generator , not a list. It will only output data if next() is called (ie by using next(csv_reader) or by using it in a for loop, like for row in csv_reader ).