Question

Python 变量代入，指定某一行截取输出字段

b=1
c=2
执行：F = ('n'.join(open('C:\\Users\\Administrator\\Desktop\\ID.txt','r').readlines()[str(b):str(c)]))
运行结果：TypeError: slice indices must be integers or None or have an __index__ method
执行：F = ('n'.join(open('C:\\Users\\Administrator\\Desktop\\ID.txt','r').readlines().decode('gbk')[b:c]))
运行结果：AttributeError: 'list' object has no attribute 'decode'
执行：F = ('n'.join(open('C:\\Users\\Administrator\\Desktop\\ID.txt','r', encoding='gbk').readlines()[b:c]))
运行结果：TypeError: 'encoding' is an invalid keyword argument for this function
各种方法都是过了还是不能正常运行，求大神帮我解惑

Answer 1

编码的话要看你py文件的编码和读取文件的编码

a=1
b=10
f=''.join(open("C:\\Users\\Administrator\\Desktop\\ID.txt").readlines()[a:b])
print f

 你第一誉族森行就基本写对了，就是穗拍list切片index只能是整形或空庆亩

Answer 2

a=1

b=10

f=''.join(open("C:\\Users\\Administrator\\Desktop\\ID.txt").readlines()[a:b])

print f

1. 使用连接竖搭世符： +

world = "World"

print "Hello " + world + " ! "

2. 使用占位符来内插

world = "World"

print "Hello %s !" % world

3.如何使用函数

li = ['my','name','is','bob']

mystr = ' '.join(li)

print mystr

4.上面的语句中字符串是作为参数传入的余肢，可以直接用变量替换：

begin_date = '2012-04-06 00:00:00'

end_date = '2012-04-06 23:59:59'

select * from usb where time between to_date(begin_date,'YYYY-MM-DD HH24:MI:SS') and to_date(end_date,'YYYY-MM-DD HH24:MI:SS')

ython 怎么在字符串中使用变量枝祥

Answer 3

encode吧
py3下式encode

追问

我用的是py2.X，能否用py2.X代码帮我解决一下？谢谢了