在Python中使用next()方法操作文件的教程
投稿:goldensun
这篇文章主要介绍了在Python中使用next()方法操作文件的教程,是Python入门中的基础知识,需要的朋友可以参考下
next()方法当一个文件被用作迭代器,典型例子是在一个循环中被使用,next()方法被反复调用。此方法返回下一个输入行,或引发StopIteration异常EOF时被命中。
与其它文件的方法,如ReadLine()相结合next()方法工作不正常。然而,usingseek()将文件重新定位到一个绝对位置将刷新预读缓冲器。
语法
以下是next()方法的语法:
fileObject.next();
参数
- NA
返回值
此方法返回下一个输入行。
例子
下面的示例演示next()方法的使用。
#!/usr/bin/python # Open a file fo = open("foo.txt", "rw+") print "Name of the file: ", fo.name # Assuming file has following 5 lines # This is 1st line # This is 2nd line # This is 3rd line # This is 4th line # This is 5th line for index in range(5): line = fo.next() print "Line No %d - %s" % (index, line) # Close opend file fo.close()
当我们运行上面的程序,它会产生以下结果:
Name of the file: foo.txt Line No 0 - This is 1st line Line No 1 - This is 2nd line Line No 2 - This is 3rd line Line No 3 - This is 4th line Line No 4 - This is 5th line