Python CSV dictReader，没有得到预期的输出

Question

下面是代码，打开文件并将其传递给 python

中的 CSV 处理程序

def csv_reader_dict():
  #Reading Data From CSV file into Dictionary using csv
  print("---------Reading Data From CSV file into Dictionary using csv------------")
  with open('input.txt','r') as file_data:
    csv_format = csv.DictReader(file_data)
    line_count2 = 0
    for row in csv_format:
        if line_count2 == 0:
            print("Header are {}".format(",".join(row) ))
            line_count2 += 1
        else:
            print("{} reside at {} and joined on {}".format(row["name"],row["address"],row["date joined"]))
            line_count2 += 1
    print("Processed {} line count".format(line_count2))
  print("------------------------------------------------------------------------")
  print("\n")

csv_reader_dict()

预期输出：

实际输出：

Answer 1

DictReader 假设第一行是 headers 所以它会跳过它。在您的代码中，您正在使用第一次迭代来打印 headers 而不是所需的信息。

将 fieldnames 添加到 DictReader 应该可以工作，因为它不会跳过第一行并且您的代码将按预期工作。

def csv_reader_dict():
#Reading Data From CSV file into Dictionary using csv
print("---------Reading Data From CSV file into Dictionary using csv------------")
with open('input.txt','r') as file_data:
    csv_format = csv.DictReader(file_data, fieldnames=['name', 'address', 'date joined'])
    line_count2 = 0
    for row in csv_format:
        if line_count2 == 0:
            print("Header are {}".format(",".join(row) ))
            line_count2 += 1
        else:
            print("{} reside at {} and joined on {}".format(row["name"],row["address"],row["date joined"]))
            line_count2 += 1
    print("Processed {} line count".format(line_count2))
print("------------------------------------------------------------------------")
print("\n")

Answer 2

当 line_count2 == 0 它遍历第一行 (john smith) 时，你在 line_count2 == 0 时强制打印 header。

您认为 print("Header are {}".format(",".join(row) )) 行打印的是 header，但它打印的是第一行的键，它们是相同的 header。

您可以简化函数：

def csv_reader_dict():
    #Reading Data From CSV file into Dictionary using csv
    print("---------Reading Data From CSV file into Dictionary using csv------------")
    with open('input.txt','r') as file_data:
        csv_format = csv.DictReader(file_data)
        line_count2 = 0
        print("Header are {}".format(",".join(csv_format.fieldnames)))
        for row in csv_format:
            print("{} reside at {} and joined on {}".format(row["name"],row["address"],row["date joined"]))
            line_count2 += 1
    print("Processed {} line count".format(line_count2))
    print("------------------------------------------------------------------------")
    print("\n")

csv_reader_dict()

Python CSV dictReader，没有得到预期的输出

Python CSV dictReader, not getting expected output

python

csv

file-handling

python-3.x

visual-studio-code

预期输出：

实际输出：