1、说明
从文件的首行首字符开始截断，截断文件为n个字符；无n表示从当前位置起截断；截断之后n后面的所有字符被删除。
2、语法
fileObject.truncate( [ size ])
3、参数
size，可选，如果存在则文件截断为 size 字节。
4、返回值
该方法没有返回值。
5、实例
#!/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
line = fo.readline()
print "Read Line: %s" % (line)
# Now truncate remaining file.
fo.truncate()
# Try to read file now
line = fo.readline()
print "Read Line: %s" % (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 Read Line: This is 1st line Read Line:
以上就是python truncate方法的介绍，在裁剪文件方面经常会使用到，可以就这种方法先进行一个练习。更多Python学习指路：python基础教程
（推荐操作系统：windows7系统、Python 3.9.1，DELL G3电脑。）
