Python读写文件(文本/二进制)的方法详解与实战

# 打开文件（只读模式）
f = open("example.txt", "r", encoding="utf-8")

# 读取内容
content = f.read()
print(content)

# 关闭文件
f.close()

open(file, mode='r', encoding=None)

with open("data.txt", "r", encoding="utf-8") as f:
    content = f.read()
    print(content)

with open("data.txt", "r", encoding="utf-8") as f:
    line = f.readline()
    while line:
        print(line.strip())  # 去掉换行符
        line = f.readline()

with open("data.txt", "r", encoding="utf-8") as f:
    lines = f.readlines()
    for line in lines:
        print(line.strip())

# 覆盖写入（原内容会被清空）
with open("output.txt", "w", encoding="utf-8") as f:
    f.write("Python 文件写入示例\n")
    f.write("第二行内容\n")

# 追加写入
with open("output.txt", "a", encoding="utf-8") as f:
    f.write("这是追加的内容\n")

# 绝对路径
f = open("/Users/admin/Desktop/data.txt", "r")

# 相对路径
f = open("subfolder/info.txt", "r")

import os
print(os.getcwd())  # 输出当前工作目录

with open("image.jpg", "rb") as f:
    data = f.read()
    print("文件大小：", len(data), "字节")

with open("image.jpg", "rb") as src:
    with open("copy.jpg", "wb") as dst:
        dst.write(src.read())
print("图片复制完成！")

try:
    with open("data.txt", "r", encoding="utf-8") as f:
        print(f.read())
except FileNotFoundError:
    print("❌ 文件不存在！")
except PermissionError:
    print("⚠️ 没有权限访问文件！")
else:
    print("✅ 文件读取成功。")
finally:
    print("操作结束。")

def count_file_info(filename):
    try:
        with open(filename, "r", encoding="utf-8") as f:
            lines = f.readlines()
            word_count = sum(len(line.split()) for line in lines)
            print(f"📘 文件行数: {len(lines)}")
            print(f"📝 总单词数: {word_count}")
    except FileNotFoundError:
        print("❌ 文件未找到！")

count_file_info("article.txt")