Question

我正在尝试解析一个csv文件，但似乎我遗漏了一些基本的东西而且无法正确使用它。 csv的每个原始包含{}中的一个字符串，包括随机排序的几个参数，如下例所示。

Timestamp,Session Index,Event,Description,Version,Platform,Device,User ID,Params,
"Dec 03, 2014 01:30 AM",1,NoRegister,,1.4.0,iPhone,Apple iPhone 5s (GSM),,{},
"Dec 03, 2014 01:30 AM",2,HomeTab,Which tab the user viewed ,1.4.0,iPhone,Apple iPhone 5s (GSM),,{ UserID : 36875; tabName : QuickAndEasy},
"Dec 03, 2014 01:30 AM",3,UserRecipeOverview,How many users go to Overview of a recipe?,1.4.0,iPhone,Apple iPhone 5s (GSM),,{ RecipeID : 1488;  UserID : 36875},

我的代码如下，但是我收到一个我不理解的错误：

counter = 0

mappedLines = {}

import csv
with open ('test.csv', 'r') as f:
    reader = csv.reader (f)

    for line in reader:
        counter = counter + 1
        lineDict = {}
        line = line.replace("{","")
        line = line.replace("}","")
        line = line.strip()
        fieldPairs = line.split(";")

        for pair in fieldPairs:
            fields = pair.split(":")
            key = fields[0].strip()
            value = fields[1].strip()
            lineDict[key] = value

        mappedLines[counter] = lineDict

def printFields(keys, lineSets):
    output_line = ""
    for key in keys:
       if key in lineSets:
           output_line = output_line + lineSets[key] + ","
       else:
           output_line += ","
    print output_line[0:len(output_line) - 1]

fields = ["UserID", "tabName", "RecipeID", "type", "searchWord", "isFromLabel"]

for key in range(1,len(mappedLines) + 1):
    lineSets = mappedLines[key]
    printFields(fields,lineSets)

这是追溯：

Traceback (most recent call last):
    File "testV3.py", line 14, in <module>
      line = line.replace("{","")
AttributeError: 'list' object has no attribute 'replace'

编辑：

我现在正在尝试使用write函数将输出保存到新的csv文件中，如下所示。 csv仅记录标题和列。

import csv


def printfields(keys, linesets):
    output_line = ""
    for key in keys:
        if key in linesets:
            output_line += linesets[key] + ","
        else:
            output_line += ","
    print output_line


def csv_writer(reader, path):
    """
    write reader to a csv file path
    """
    with open(path, "wd") as csv_file:
        writer = csv.writer(csv_file, delimiter=",")
        for line1 in line:
            if line1 in path
            writer.writerow(line1)

if __name__ == "__main__":
    fields = [
        "UserID", "tabName", "RecipeID", "type", "searchWord", "isFromLabel", "targetUID"
    ]
    mappedLines = {}
    with open('test.csv', 'r') as f:
        reader = csv.DictReader(f)
        for line in reader:
            fieldPairs = [
                p for p in
                line['Params'].strip().strip('}').strip('{').strip().split(';')
                if p
            ]
            lineDict = {
                pair.split()[0].strip(): pair.split(':')[1].strip()
                for pair in fieldPairs
            }
            mappedLines[reader.line_num] = lineDict
        path = "output.csv"
        csv_writer(reader, path)

    for key in sorted(mappedLines.keys()):
        linesets = mappedLines[key]
        printfields(fields, linesets)

Answer 1

line是包含当前行的单元格的列表。要访问其中一个，请使用循环：

for cell in line:
    cell.replace(...)

Answer 2

您可以使用以下语句删除＆＃34; {＆＃34;和＆＃34;}＆＃34;在字符串

列表中

line = ".".join(line).replace("{","").replace("}","").split(",")

Answer 3

我重新安排了您的代码并对其进行了修改。更改是它使用csv.DictReader，并且不再使用计数器变量。并且不再使用for循环中的range函数。

import csv


def printFields(keys, lineSets):
    output_line = ""
    for key in keys:
        if key in lineSets:
            output_line += lineSets[key] + ","
        else:
            output_line += ","
    print output_line


if __name__ == "__main__":
    fields = [
        "UserID", "tabName", "RecipeID", "type", "searchWord", "isFromLabel"
    ]
    mappedLines = {}
    with open('test.csv', 'r') as f:
        reader = csv.DictReader(f)
        for line in reader:
            fieldPairs = [
                p for p in
                line['Params'].strip().strip('}').strip('{').strip().split(';')
                if p
            ]
            lineDict = {
                pair.split()[0].strip(): pair.split(':')[1].strip()
                for pair in fieldPairs
            }
            mappedLines[reader.line_num] = lineDict

    for key in sorted(mappedLines.keys()):
        lineSets = mappedLines[key]
        printFields(fields, lineSets)

解析python和csv模块中的csv文件

3 个答案: