#coding=utf8
import cStringIO
import StringIO
import time
values = []
items = ['1,2,31,2,31,2,31,2,3'] * 10000000
#print items
st = float(time.time())
for i in items:
values.append(i)
news = ''.join(values)
print len(news)
print 'list append cost time:%s'%(float(time.time()) - st)
strio = cStringIO.StringIO()
st = float(time.time())
for j in items:
strio.write(j)
print len(strio.getvalue())
print 'cStringIO cost time:%s'%(float(time.time()) - st)
strio = StringIO.StringIO()
st = float(time.time())
for j in items:
strio.write(j)
print len(strio.getvalue())
print 'StringIO cost time:%s'%(float(time.time()) - st)
![](//images0.cnblogs.com/blog/409157/201304/12164323-530e4fb9410b4f84b4db82b0abab6e37.gif)