为什么使用.reader（）跳过第一行而.readlines（）不是？

Question

I am attempting to read in all the data from a .csv file. First, I tried using csv.reader(), but this would skip the first line of my file. I was able to remedy this using .readlines(), but I am wondering why this happens with .reader() and would like to make it read my first line.

import glob
import csv

new_cards = []
path = 'C:\\Users\\zrc\\Desktop\\GCData2\\*.asc'
files = glob.glob(path)


# First Method

for name in files:
    with open(name) as f:
        for line in f:
            reader = csv.reader(f, delimiter=',', quoting=csv.QUOTE_NONE)
            for row in reader:
                new_cards.append(row)
print(len(new_cards))


# Second Method

for name in files:
    with open(name) as f:
        m = f.readlines()
        for line in m:
            new_cards.append(line)

print(len(new_cards))

Answer 1

In your first function you dont need to use for line in f: this line is taking your first line and then the reader starts from the second.

The correct way should be:

for name in files:
    with open(name) as f:
        reader = csv.reader(f, delimiter=',', quoting=csv.QUOTE_NONE)
        for row in reader:
            new_cards.append(row)
print(len(new_cards))

You dont need to iterate over each line in the first one because you are already doing it with for row in reader: