发出读取csv文件

这是因为在下面的行中-row_count = sum(1 for row in data)-您已经阅读了文件，并且它已经到达了它的结尾。 所以当你再次尝试做-

for row in data:
    print r

它不起作用，因为data文件在最后。

您可以尝试的许多事情之一是重新打开文件以从头开始读取它。

例子： -

import csv
with open('blah.csv','rb') as csvfile:
    data = csv.reader( csvfile )
    row_count = sum(1 for row in data)
    print row_count

with open('blah.csv','rb') as csvfile:
    data = csv.reader( csvfile )
    r = 1
    for row in data:
        print r

虽然你也可以同时计数行和打印行到一个单一的循环，如 -

import csv
with open('blah.csv','rb') as csvfile:
    data = csv.reader( csvfile )
    row_count = 0
    for row in data
        row_count += 1
        print row
    print row_count

你可以做的另一件事是 -

csvfile.seek(0) #to make the file point to the start.

例子： -

import csv
with open('blah.csv','rb') as csvfile:
    data = csv.reader( csvfile )
    row_count = sum(1 for row in data)
    print row_count
    csvfile.seek(0)
    r = 1
    for row in data:
        print r