# Author:larlly
'''
函数
1.在Python交互式命令行下，可以直接输入代码，然后执行，并立刻得到结果。
2.文本编辑器推荐俩款
http://www.sublimetext.com/
https://notepad-plus-plus.org/
3.python运行助手 learning.py
1 # Author:larlly
2 # python运行助手
3 r'''
4 learning.py
5
6 A Python 3 tutorial from http://www.liaoxuefeng.com
7
8 Usage:
9
10 python3 learning.py
11 '''
12
13 import sys
14
15 def check_version():
16 v = sys.version_info
17 if v.major == 3 and v.minor >= 4:
18 return True
19 print('Your current python is %d.%d. Please use Python 3.4.' % (v.major, v.minor))
20 return False
21
22 if not check_version():
23 exit(1)
24
25 import os, io, json, subprocess, tempfile
26 from urllib import parse
27 from wsgiref.simple_server import make_server
28
29 EXEC = sys.executable
30 PORT = 39093
31 HOST = 'local.liaoxuefeng.com:%d' % PORT
32 TEMP = tempfile.mkdtemp(suffix='_py', prefix='learn_python_')
33 INDEX = 0
34
35 def main():
36 httpd = make_server('127.0.0.1', PORT, application)
37 print('Ready for Python code on port %d...' % PORT)
38 httpd.serve_forever()
39
40 def get_name():
41 global INDEX
42 INDEX = INDEX + 1
43 return 'test_%d' % INDEX
44
45 def write_py(name, code):
46 fpath = os.path.join(TEMP, '%s.py' % name)
47 with open(fpath, 'w', encoding='utf-8') as f:
48 f.write(code)
49 print('Code wrote to: %s' % fpath)
50 return fpath
51
52 def decode(s):
53 try:
54 return s.decode('utf-8')
55 except UnicodeDecodeError:
56 return s.decode('gbk')
57
58 def application(environ, start_response):
59 host = environ.get('HTTP_HOST')
60 method = environ.get('REQUEST_METHOD')
61 path = environ.get('PATH_INFO')
62 if method == 'GET' and path == '/':
63 start_response('200 OK', [('Content-Type', 'text/html')])
64 return [b'<html><head><title>Learning Python</title></head><body><form method="post" action="/run"><textarea name="code" style="90%;height: 600px"></textarea><p><button type="submit">Run</button></p></form></body></html>']
65 if method == 'GET' and path == '/env':
66 start_response('200 OK', [('Content-Type', 'text/html')])
67 L = [b'<html><head><title>ENV</title></head><body>']
68 for k, v in environ.items():
69 p = '<p>%s = %s' % (k, str(v))
70 L.append(p.encode('utf-8'))
71 L.append(b'</html>')
72 return L
73 if host != HOST or method != 'POST' or path != '/run' or not environ.get('CONTENT_TYPE', '').lower().startswith('application/x-www-form-urlencoded'):
74 start_response('400 Bad Request', [('Content-Type', 'application/json')])
75 return [b'{"error":"bad_request"}']
76 s = environ['wsgi.input'].read(int(environ['CONTENT_LENGTH']))
77 qs = parse.parse_qs(s.decode('utf-8'))
78 if not 'code' in qs:
79 start_response('400 Bad Request', [('Content-Type', 'application/json')])
80 return [b'{"error":"invalid_params"}']
81 name = qs['name'][0] if 'name' in qs else get_name()
82 code = qs['code'][0]
83 headers = [('Content-Type', 'application/json')]
84 origin = environ.get('HTTP_ORIGIN', '')
85 if origin.find('.liaoxuefeng.com') == -1:
86 start_response('400 Bad Request', [('Content-Type', 'application/json')])
87 return [b'{"error":"invalid_origin"}']
88 headers.append(('Access-Control-Allow-Origin', origin))
89 start_response('200 OK', headers)
90 r = dict()
91 try:
92 fpath = write_py(name, code)
93 print('Execute: %s %s' % (EXEC, fpath))
94 r['output'] = decode(subprocess.check_output([EXEC, fpath], stderr=subprocess.STDOUT, timeout=5))
95 except subprocess.CalledProcessError as e:
96 r = dict(error='Exception', output=decode(e.output))
97 except subprocess.TimeoutExpired as e:
98 r = dict(error='Timeout', output='执行超时')
99 except subprocess.CalledProcessError as e:
100 r = dict(error='Error', output='执行错误')
101 print('Execute done.')
102 return [json.dumps(r).encode('utf-8')]
103
104 if __name__ == '__main__':
105 main()
需要支持HTML5的浏览器：
IE >= 9
Firefox
Chrome
Sarafi
输出函数 print()
输入函数 input()
退出函数 exit()
3.x默认支持中文 2.x需要添加 #-*- coding:utf-8 -*-
'''
print('100 + 200 =',100+200 )
print("hello world ","你好，世界")
print(1024 * 768)
#python基础
#print absolute value of an integet
a = 100
if a>=0:
print(a)
else:
print(-a)
#print 俩行\ \本身也需要转义
print('\\\n\\')
#转义太多，可以考虑r''
print(r'\\\\t\\')
#如果字符串内部有很多换行，用\n写在一行里不好阅读，为了简化，Python允许用'''...'''的格式表示多行内容
print('''line1
... line2
... line3''')
#上面是在交互式命令行内输入，注意在输入多行内容时，提示符由>>>变为...，提示你可以接着上一行输入。如果写成程序，就是：
print('''line1
line2
line3''')
#多行字符串'''...'''还可以在前面加上r使用
#布尔值可以用and/or/not 对应 与/或/非
print(True)
print(False)
print(True and False)
print(True or False)
print(not True)
#在Python中，通常用全部大写的变量名表示常量：
#运算符/和//， /计算结果浮点数， //地板除，结果是整数
print(10/3)
print(10//3)
#字符编码
# ASCII 一个字节 GB2312 Unicode 俩个字节 GBK GB18030 utf-8 可变长编码
#对于单个字符的编码，Python提供了ord()函数获取字符的整数表示，chr()函数把编码转换为对应的字符
print(ord('A'))
print(ord("中"))
print(chr(123))
#以Unicode表示的str通过encode()方法可以编码为指定的bytes，
name = 'abc'
print(name.encode('ascii'))
name1 = '且听风吟'
print(name1.encode('utf-8'))
#我们从网络或磁盘上读取了字节流，那么读到的数据就是bytes。要把bytes变为str，就需要用decode()方法：
#name2 = "b'abc'"
#name3 = "b'\xe4\xb8\x94\xe5\x90\xac\xe9\xa3\x8e\xe5\x90\x9f'" 且听风吟的字节
print(b'abc'.decode('ascii'))
print(b'\xe4\xb8\x94\xe5\x90\xac\xe9\xa3\x8e\xe5\x90\x9f'.decode('utf-8'))
#计算str长度(即字节数)函数 len()
print(len(b'abc'))
print(len(b'\xe4\xb8\x94\xe5\x90\xac\xe9\xa3\x8e\xe5\x90\x9f'))
print(len("且听分吟".encode('utf-8')))
#可见，1个中文字符经过UTF-8编码后通常会占用3个字节，而1个英文字符只占用1个字节
#py文件中申明了utf-8编码并不意味着你的.py文件就是UTF-8编码的，必须并且要确保文本编辑器正在使用UTF-8 without BOM编码