文件操作练习

1.有如下文件,a1.txt,里面的内容为:
老男孩是最好的学校,
全心全意为学生服务,
只为学生未来,不为牟利。
我说的都是真的。哈哈
分别完成以下的功能:
a,将原文件全部读出来并打印。
b,在原文件后面追加一行内容:信不信由你,反正我信了。
c,将原文件全部读出来,并在后面添加一行内容:信不信由你,反正我信了。
d,将原文件全部清空,换成下面的内容:
每天坚持一点,
每天努力一点,
每天多思考一点,
慢慢你会发现,
你的进步越来越大。

with open("a1","r",encoding="utf-8") as fa,open("a1","a",encoding="utf-8") as fb:
    print(fa.read())
    fb.write("\n信不信由你,反正我信了。")
with open("a1","r+",encoding="utf-8") as fc:
    print(fc.read())
    fc.write("\n信不信由你,反正我信了。")

with open("a1","w",encoding="utf-8") as fd:
    fd.write("""每天坚持一点,
每天努力一点,
每天多思考一点,
慢慢你会发现,
你的进步越来越大。""")

2.有如下文件,t1.txt,里面的内容为:
葫芦娃,葫芦娃,
一根藤上七个瓜
风吹雨打,都不怕,
啦啦啦啦。
我可以算命,而且算的特别准:
上面的内容你肯定是心里默唱出来的,对不对?哈哈
分别完成下面的功能:
a,以r的模式打开原文件,利用for循环遍历文件句柄。
b,以r的模式打开原文件,以readlines()方法读取出来,并循环遍历 readlines(),并分析a,与b 有什么区别?深入理解文件句柄与 readlines()结果的区别。
c,以r模式读取‘葫芦娃,’前四个字符。
d,以r模式读取第一行内容,并去除此行前后的空格,制表符,换行符。
e,以a+模式打开文件,先追加一行:‘老男孩教育’然后在从最开始将 原内容全部读取出来。

with open("t1.txt","r",encoding="utf-8") as fa:
    for i in fa:
        print(i.strip())
with open("t1.txt","r",encoding="utf-8") as fb:
    for i in fb.readlines():
        print(i.strip())
#a相当于按段打印了一个字符串   b是循环打印一个列表
with open("t1.txt","r",encoding="utf-8") as fc:
    print(fc.read(4))
with open("t1.txt","r",encoding="utf-8") as fd:
    print(fd.readline().strip())
with open("t1.txt","a+",encoding="utf-8") as fe:
    fe.write("\n老男孩教育")
    fe.seek(0)
    print(fe.read())

3.文件a.txt内容:每一行内容分别为商品名字,价钱,个数。
apple 10 3
tesla 100000 1
mac 3000 2
lenovo 30000 3
chicken 10 3
通过代码,将其构建成这种数据类型:[{'name':'apple','price':10,'amount':3},{'name':'tesla','price':1000000,'amount':1}......] 并计算出总价钱。

with open("a.txt","r",encoding="utf-8") as f:
    lst = f.readlines()
lst_sum = []
sum = 0
for i in lst:
    dic ={}
    ls =i.split(" ")
    dic["name"] = ls[0]
    dic["price"] = int(ls[1])
    dic["amoubt"] = int(ls[2])
    sum += int(ls[1])*int(ls[2])
    lst_sum.append(dic)
print(lst_sum)
print(sum)

4.有如下文件:
alex是老男孩python发起人,创建人。
alex其实是人妖。
谁说alex是sb?
你们真逗,alex再牛逼,也掩饰不住资深屌丝的气质。
将文件中所有的alex都替换成大写的SB(文件的改的操作)。

with open("alex","r",encoding="utf-8") as f1,open("alex1","w",encoding="utf-8") as f2:
    string = f1.read()
    string = string.replace("alex","SB")
    f2.write(string)
import os
os.rename("alex","alex2")
os.rename("alex1","alex")

5.文件a1.txt内容(选做题)

name:apple price:10 amount:3 year:2012
name:tesla price:100000 amount:1 year:2013
.......

通过代码,将其构建成这种数据类型:
[{'name':'apple','price':10,'amount':3,year:2012},
{'name':'tesla','price':1000000,'amount':1}......]
并计算出总价钱。

with open("a1.txt","r",encoding="utf-8") as f:
    lst = f.readlines()
lst_num = []
for i in lst:
    ls = i.strip().split(" ")
    dic = {}
    for j in ls:
        k,v=j.split(":")
        if v.isdecimal():
            dic[k] = int(v)
        else:
            dic[k] = v
    lst_num.append(dic)
print(lst_num)

6.文件a1.txt内容(选做题)
序号 部门 人数 平均年龄 备注
1 python 30 26 单身狗
2 Linux 26 30 没对象
3 运营部 20 24 女生多
.......

通过代码,将其构建成这种数据类型:
[{'序号':'1','部门':Python,'人数':30,'平均年龄':26,'备注':'单身狗'},
......]

 with open("a11.txt","r",encoding="utf-8") as f:
    string = f.readline()
    lst = f.readlines()
lst1 = string.strip().split(" ")
lst_num = []
for i in lst:
    lst2 = i.strip().split(" ")
    dic = {}
    for j in range(len(lst2)):
        if lst2[j].isdecimal():
            dic[lst1[j]] = int(lst2[j])
        else:
            dic[lst1[j]] = lst2[j]
    lst_num.append(dic)
print(lst_num)
原文地址:https://www.cnblogs.com/ciquankun/p/11191826.html