如何在同一個“for”循環中轉到CSV文件的第一個記錄？

Question

我在這里問了一個類似的問題，我得到的答案是使用seek()方法。 現在我正在做以下事情：

with open("total.csv", 'rb') as input1:
    time.sleep(3)
    input1.seek(0)
    reader = csv.reader(input1, delimiter="\t")
    for row in reader:
       #Read the CSV row by row.

但是，我想在同一個for循環中導航到CSV的第一條記錄。 我知道我的循環不會以這種方式終止，但這正是我想要的。 我不希望for循環結束，如果它到達最后一條記錄，我想導航回第一條記錄並重新讀取整個文件（並繼續閱讀）。 我怎么做？

謝謝！

Answer 1

它必須在for -loop中嗎？ 您可以像這樣（未經測試）實現此行為：

with open("total.csv", 'rb') as input1:
    time.sleep(3)
    reader = csv.reader(input1, delimiter="\t")
    while True:
        input1.seek(0)
        for row in reader:
            #Read the CSV row by row.

Answer 2

為簡單起見，創建一個生成器：

def repeated_reader(input, reader):
    while True:
        input.seek(0)
        for row in reader:
            yield row

with open("total.csv", 'rb') as input1:
    reader = csv.reader(input1, delimiter="\t")
    for row in repeated_reader(input1, reader):
        #Read the CSV row by row.

Answer 3

我實際上計算了CSV中的總行數，當我在最后一行時，我做了input1.seek(0)

row_count = sum(1 for row in csv.reader(open('total.csv')))
print row_count


row_count2 = 0

with open("total.csv", 'rb') as input1:
        time.sleep(3)
        input1.seek(0)
        reader = csv.reader(input1, delimiter="\t") 
        for row in reader:
            count += 1
            #Read the CSV row by row.
            if row_count2 == row_count:
                row_count2 = 0
                time.sleep(3)
                input1.seek(0)