1 1.open使用open打开文件后一定要记得调用文件对象的close()方法。比如可以用try/finally语句来确保最后能关闭文件。 2 file_object = open('thefile.txt') 3 try: 4 all_the_text = file_object.read( ) 5 finally: 6 file_object.close( ) 7 注:不能把open语句放在try块里,因为当打开文件出现异常时,文件对象file_object无法执行close()方法。 8 2.读文件读文本文件input = open('data', 'r') 9 #第二个参数默认为r10 input = open('data')11 12 读二进制文件input = open('data', 'rb')13 读取所有内容file_object = open('thefile.txt')14 try:15 all_the_text = file_object.read( )16 finally:17 file_object.close( )18 读固定字节file_object = open('abinfile', 'rb')19 try:20 while True:21 chunk = file_object.read(100)22 if not chunk:23 break24 do_something_with(chunk)25 finally:26 file_object.close( )27 读每行list_of_all_the_lines = file_object.readlines( )28 如果文件是文本文件,还可以直接遍历文件对象获取每行:29 for line in file_object:30 process line31 3.写文件写文本文件output = open('data.txt', 'w')32 写二进制文件output = open('data.txt', 'wb')33 追加写文件output = open('data.txt', 'a')34 35 output .write("\n都有是好人")36 37 output .close( )38 39 写数据file_object = open('thefile.txt', 'w')40 file_object.write(all_the_text)41 file_object.close( )