注意:现在python3.3.5中print打印语句有了新写法:
1. python指定生成随机数
>>> import random >>> >>> #正确测print写法 >>> rand = random.randint(1,500) >>> print (rand) 343 >>> #错误的print语法: >>> print rand SyntaxError: invalid syntax >>>
2. #python对文件操作
1.生成随机数 import random #这个是注释,引入模块 rnd = random.randint(1,500)#生成1-500之间的随机数 2.读文件 f = open("c:\1.txt","r") lines = f.readlines()#读取全部内容 for line in lines print line 3.写文件 f = open("c:\1.txt","r+")#可读可写模式 f.write("123")#写入字符串 4.正则表达式,读取tomcat的日志并打印日期 import re regx = "dddd-dd-d+" f = open("c:stdout.log","r") i = 0 for str in f.readlines(): if re.search(regx,str): Response.write(str+"<br>") if i>10:break#由于是测试,只分析十行 i=i+1 f.close(); 5.连接数据库 import pgdb conn = pgdb.connect (host='localhost',databse='qingfeng',user='qingfeng',password='123') cur = conn.cursor() cur.execute("select * from dream") print cur.rowcount 6.SAX处理xml: import string from xml.sax import saxlib, saxexts class QuotationHandler(saxlib.HandlerBase): """Crude sax extractor for quotations.dtd document""" def __init__(self): self.in_quote = 0 self.thisquote = '' def startDocument(self): print '--- Begin Document ---' def startElement(self, name, attrs): if name == 'quotation': print 'QUOTATION:' self.in_quote = 1 else: self.thisquote = self.thisquote + '{' def endElement(self, name): if name == 'quotation': print string.join(string.split(self.thisquote[:230]))+'...', print '('+str(len(self.thisquote))+' bytes) ' self.thisquote = '' self.in_quote = 0 else: self.thisquote = self.thisquote + '}' def characters(self, ch, start, length): if self.in_quote: self.thisquote = self.thisquote + ch[start:start+length] if __name__ == '__main__': parser = saxexts.XMLParserFactory.make_parser() handler = QuotationHandler() parser.setDocumentHandler(handler) parser.parseFile(open("sample.xml")) parser.close() 7.python的GUI模块标准的是Tkinter,也有QT和MFC的模块,有兴趣的大家自己搜索下 import Tkinter root=Tkinter.Tk() my=Label(root,"Welcome to python's world") my.pack() root.mainloop()