Python取子字符串方法

sfsfsd345#-3sfsfsd3.4me

345#-3出来

Python自定义函数的写法如下所示:

>>> ================================ RESTART ================================
>>> def getsubstr(txt_s):
#处理换行符问题
t=txt_s
findex=txt_s.find('#')
s_len=len(txt_s)
t=t[0:findex]
dkbh=''
bh_s=''
for a in t:
#获取是数字 中划线 下划线的子字符串
if(a.isdigit()==True or a=='-' or a=='_'):
if(dkbh==''):
dkbh=a
else:
dkbh+=a
s=txt_s[findex+1:findex+2]
if(s=='-'):
s=txt_s[findex+1:s_len]
for b in s:
if(b.isdigit()==True or b=='-' or b=='_'):
if(bh_s==''):
bh_s=b
else:
bh_s+=b
else:
break
dkbh+='#'+bh_s
return dkbh

>>> print getsubstr('sfsfsd345#-3sfsfsd3.4men')
345#-3
>>>

>>> ================================ RESTART ================================
>>> def getAreaVal(txt_s):
findex=txt_s.find('#')
s_len=len(txt_s)
rb=''
bh_s=''
s=txt_s[findex+1:findex+2]
if(s=='-'):
s=txt_s[findex+1:s_len]
for b in s:
if(b.isdigit()==True or b=='-' or b=='_'):
if(bh_s==''):
bh_s=b
else:
bh_s+=b
else:
break
q=txt_s[findex+1:s_len]
for c in q:
if(c.isdigit()==True or c=='-' or c=='_' or c=='.'):
if(rb==''):
rb=c
else:
rb+=c
else:
continue
return rb.replace(bh_s,'')

>>> print getAreaVal('sfsdfd45#-2sfdfs45.6men')
45.6
>>>