文件处理 · 4个练习

练习1 · 英汉词典读取英汉词典.py

读取英汉词典.txt，构建字典，英文→中文查询，quit 退出

""" 英汉词典读取 """
with open("英汉词典.txt", encoding="utf8") as f:
    eng_dict = {}
    for line in f:
        line = line.rstrip()
        fields = line.split(",")
        if len(fields) == 2:
            eng_dict[fields[0]] = fields[1]

while True:
    info = input("请输入英文词语: ")
    if info == "quit": break
    if info in eng_dict:
        print("汉语：", eng_dict[info])
    else:
        print("没有这个词语")

练习2 · 婚礼礼金程序文件的婚礼礼金程序.py

写入婚礼礼金.txt，quit 后统计加和/最高/最低/平均

""" 婚礼礼金程序 """
fname = "婚礼礼金.txt"
with open(fname, "w", encoding="utf8") as f:
    while True:
        info = input("请输入来人和金额: ")
        if info == "quit": break
        fields = info.split()
        if len(fields) == 2:
            name, money = fields
            f.write(f"{name},{int(money)}\n")

with open(fname, encoding="utf8") as f:
    moneys = []
    for line in f:
        fields = line.rstrip().split(",")
        if len(fields) == 2:
            moneys.append(int(fields[1]))
    print("加和:", sum(moneys))
    print("最高:", max(moneys))
    print("最低:", min(moneys))
    print("平均:", sum(moneys)/len(moneys))

练习3 · 成绩录入 JSON 成绩录入json.py

加载/保存成绩录入json.txt，JSON格式存储

""" 成绩录入 JSON """
import os, json
file_name = "成绩录入json.txt"
grade_dict = {}
if os.path.exists(file_name):
    with open(file_name, encoding="utf8") as f:
        grade_dict = json.loads(f.read())

while True:
    info = input("请输入姓名和成绩: ")
    if info == "quit": break
    fields = info.split()
    if len(fields) == 2:
        name, grade = fields
        grade_dict[name] = int(grade)

with open(file_name, "w", encoding="utf8") as f:
    f.write(json.dumps(grade_dict))

练习4 · 异常处理成绩录入异常处理学生成绩录入程序.py

try/except 捕获非数字异常，程序不退出

""" 异常处理成绩录入 """
file_name = "学生成绩带异常处理.txt"
with open(file_name, "w", encoding="utf8") as f:
    while True:
        info = input("请输入姓名和成绩: ")
        try:
            if info == "quit": break
            name, grade = info.split()
            grade = int(grade)
        except Exception as e:
            print("出现问题了：", e, "你输入的是：", info)
            continue
        f.write(f"{name},{grade}\n")
print("success")

文件处理 · 4练习