python 4-4 如何将多个小字符串拼接成一个大的字符串字符串(+)/S.join()

+ 通过运算符重载

a = "hello"
b = "wolrd"
c = a + b
print c
'helloworld'
s = ''
lista = [ "hello","world",123,456,"xyz" ]
for tempstr in lista:
s += str(tempstr)
print s
'helloworldhelloworld123456xyz'

通过S.join()来连接,S是连接字符的分隔符

s = ''
lista = [ "hello","world",123,456,"xyz" ]
s = ''.join( [str(x) for x in lista ]
通过列表解析会带来新的列表空间生成,可以使用生成器
s = ''.join((str(x) for x in lista))

help(str.join)

>>> help(str.join)
Help on method_descriptor:

join(...)
S.join(iterable) -> string

Return a string which is the concatenation of the strings in the
iterable.  The separator between elements is S.