Python 读取,写入 txt 文本内容

1, 读取

python常用的读取文件函数有三种read(), readline(), readlines()

1.1 read()

一次性读取文本中全部的内容, 以字符串的形式返回结果

with open('people.txt','r') as f:
    data=f.read()
    print(data)

huawei
alibaba
baidu

1.2 readline()

只读取文本第一行的内容，以字符串的形式返回结果

with open('people.txt','r') as f:
    data=f.readline()
    print(data)

huawei

1.3 readlines()

读取文本所有内容, 并且以数列的格式返回结果, 一般配合 for in 使用

with open('people.txt','r') as f:
    data=f.readlines()
    print(data)
    for line in data:
        print(line.strip('\n'))

['huawei\n', 'alibaba\n', 'baidu']
huawei
alibaba
baidu

2, 写入

2.1 存在则覆盖,不存在则创建

with open('people.txt','w') as f:
    f.write('这是个测试!')

2.2 存在则报错,不存在则创建

with open('people.txt','x') as f:
    f.write('这是个测试!')

2.3 存在则追加,不存在则创建

with open('people.txt','x') as f:
    f.write('这是个测试!')

3, 读写模式

    ========= ===============================================================
    Character Meaning
    --------- ---------------------------------------------------------------
    'r'       open for reading (default)
    'w'       open for writing, truncating the file first
    'x'       create a new file and open it for writing
    'a'       open for writing, appending to the end of the file if it exists
    'b'       binary mode
    't'       text mode (default)
    '+'       open a disk file for updating (reading and writing)
    'U'       universal newline mode (deprecated)
    ========= ===============================================================
    The default mode is 'rt' (open for reading text). For binary random
    access, the mode 'w+b' opens and truncates the file to 0 bytes, while
    'r+b' opens the file without truncation. The 'x' mode implies 'w' and
    raises an `FileExistsError` if the file already exists.