csv文件讀寫處理

1.讀取

第一種：

import csv
with open("route.csv","r") as f:
    #reader是一個迭代器
    reader=csv.reader(f)
    next(reader)  #輸出結果會去掉行頭標題
    for row in reader:
        name=row[0]
        dates=row[-1]
        print({"name":name,"date":dates})

第二種：字典方式讀取

import csv
with open("route.csv","r") as f:
    #使用DictReader創建的reader是一個迭代器，遍歷迭代器返回的數據是一個字典(有序字典)
    #返回的結果不包含行首的標題
    reader=csv.DictReader(f)
    for row in reader:
        # print(row) #遍歷迭代器返回的數據是一個字典(有序字典)
        print(row["昵稱"],row["院系信息"])

 2.寫入

第一種：

import csv
headers=["username","age","addr"]
values={
    ("張三",23,"滿城"),
    ("李四",24,"保定"),
    ("王五",25,"衡水"),
    ("趙六",26,"邯鄲")
}
with open("name.csv","w",encoding="utf-8",newline="") as f: #newline換行符為空，默認為\n
    writer=csv.writer(f)
    writer.writerow(headers) #寫入行首標題
    writer.writerows(values) #寫入多行

第二種：

import csv
headers=["username","age","addr"]
values=[
    {"username":"張三","age":23,"addr":"保定"},
    {"username":"李四","age":23,"addr":"邯鄲"},
    {"username":"王五","age":23,"addr":"石家庄"},
    {"username":"趙六","age":23,"addr":"衡水"},
]

with open("name2.csv","w",encoding="utf-8",newline="") as f:
    writer=csv.DictWriter(f,headers)
    #寫入表頭的時候需要寫入writerheader方法
    writer.writeheader()
    writer.writerows(values)