python1

1.数据类型

list 列表[1,2,3]
tuple 元组(1,2,3)
dict 字典{"key1":"value1", "key2":"value2"}

2.字符串类型转换

a = "哈哈".decode("utf-8")

3.字符串拼接，%s 字符串的占位符，%d 数值的占位符

a = "my name is %s dulianyong" % "world's"

print a 输入结果my name is world's dulianyong

a = "this is {} {}".format("my", "borther")

a = "this is {0} {1}".format("my", "apple")

a = "this is {ss} {kk}".format(ss = "my", kk"apple" = "apple")

a = "this is %(w)s %(t)s" % {"w":"my", "t":"apple"}

4.字符串拼接join

a = "a"
b = "sssssssssss"
c = "151sfsdfsdf"
"".join([a,b,c])
'asssssssssss151sfsdfsdf'
",".join([a,b,c])
'a,sssssssssss,151sfsdfsdf'

5.读写文件

w:write;r:read;a:append

写：

d = open("a.txt", "w")

d.write("hi. second hi.")

d.close()

读：

d = open("a.txt", "r")

d.readline()//读取一行

d.read(10)//读取十行

d.seek(0)//游标回到第一行

import linecache 使用linecache读取文件，返回的是元组

print linecache.getline("a.txt", 1)

print linecache.getlines("a.txt")