> For the complete documentation index, see [llms.txt](https://hezhiqiang8909.gitbook.io/python-ai/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://hezhiqiang8909.gitbook.io/python-ai/08_file.md).

# 文件

## 文件扩展名

* web文件：.html, .css, .js, .xml, .json
* 程序：.php, .py, .rb, .c, .cc
* 视频：.flv, avi, .rmvb, .mp4, .mkv, .3gp
* 音频：.wmv, .mp3, .flue, .mid
* 其他：.pdf, .chm

## 文件操作

> 以存储文件编码方式方式打开文件

* 举例：以GBK保存的文件，以GBK编码方式打开
* Pycharm 默认 utf-8文件创建并存储
* 文件编码和文件内容编码必须要统一，否则打开文件会显示乱码内容

```python
# utf-8编码方式打开，Python3 字符串以unicode编码，unicode 隐式转换为 utf-8
# open函数内部 byte 类型转化为 str类型
f = open(filePath, mode='r', encoding='utf-8')
f = open(filePath, mode='r', encoding='GBK')
```

### mode

* r: 读取
* rb: 二进制读取
* str 转 bytes : `"中文".encode('utf-8')`

```python
f = open('/path/to/SOMEFILE', mode, encode='utf8')
data = f.read(5)  # 5个字符
f.close()
```

* 读取一行：`f.readline()`
* 读取所有行以列表显示

```python
for i in f.readlines():
  print(i.strip())
```

* 列表连接成字符串

```python
''.join([.strip(), 'iiii'])
```

* 文件对象转换成迭代器: `for i in enumerate(f.readlines()):`
* 返回指针位置: `f.tell()`
* 移动指针到起始首行: `f.seek(0)`
* with语句不用关闭close()方法

```python
with open(/path/to/somefile, r) as f,open(/path/to/somefile, w) as f2 :
  f.read()
  f2.write()
```