use string command to match many digitals

hello.,Aaron

 

glad to see your reply

 

sorry for my bad question

 

 

actually what I want to achieve is:

 

 

I need to check whether one pattern is number(s) or not

 

 

for example:

 

/cjj/xx/123456/xx

 

/cjj/xx/23tz/xx

 

 

the first /cjj/xx/123456/xx is what I want because I need to do some action to this 123456

 

23tz is not I want,I need pure number in that palce

 

 

string is

 

 

digit or interger?

 

I don't know the difference between them

 

the number what I mean is 0-9 .0-9 is number I mean

 

which command should I use ? digit or interger?