在python列表中获取带有解析的字符串

Question

i have list like this

["<name:john student male age=23 subject=\computer\sience_{20092973}>",
"<name:Ahn professor female age=61 subject=\computer\math_{20092931}>"]

i want to get student using {20092973},{20092931}.

so i want to split to list like this

my expect result 1 is this (input is {20092973})

"student"

my expect result 2 is this (input is {20092931})

"professor"

i already searching... but i can't find.. sorry..

how can i this?

Answer 1

I don't think you should be doing this in the first place. Unlike your toy example, your real problem doesn't involve a string in some clunky format; it involves a Scapy NetworkInterface object. Which has attributes that you can just access directly. You only have to parse it because for some reason you stored its string representation. Just don't do that; store the attributes you actually want when you have them as attributes.

The NetworkInterface object isn't described in the documentation (because it's an implementation detail of the Windows-specific code), but you can interactively inspect it like any other class in Python (eg, dir(ni) will show you all the attributes), or just look at the source . The values you want are name and win_name . So, instead of print ni , just do something like print '%s,%s' % (ni.name, ni.win_name) . Then, parsing the results in some other program will be trivial, instead of a pain in the neck.

Or, better, if you're actually using this in Scapy itself, just make the dict directly out of {ni.win_name: ni.name for ni in nis} . (Or, if you're running Scapy against Python 2.5 or something, dict((ni.win_name, ni.name) for ni in nis) .)

---

But to answer the question as you asked it (maybe you already captured all the data and it's too late to capture new data, so now we're stuck working around your earlier mistake…), there are three steps to this: (1) Figure out how to parse one of these strings into its component parts. (2) Do that in a loop to build a dict mapping the numbers to the names. (3) Just use the dict for your lookups.

For parsing, I'd use a regular expression. For example:

<name:\S+\s(\S+).*?\{(\d+)\}>

Debuggex Demo

Now, let's build the dict:

r = re.compile(r'<name:\S+\s(\S+).*?\{(\d+)\}>')
matches = (r.match(thing) for thing in things)
d = {match.group(2): match.group(1) for match in matches}

And now:

>>> d['20092973']
'student'

Answer 2

Code:

def grepRole(role, lines):   
    return [line.split()[1] for line in lines if role in line][0]

l = ["<name:john student male age=23 subject=\computer\sience_{20092973}>",
     "<name:Ahn professor female age=61 subject=\compute\math_{20092931}>"]
print(grepRole("{20092973}", l))
print(grepRole("{20092931}", l))

Output:

student
professor

Answer 3

current_list = ["<name:john student male age=23 subject=\computer\sience_{20092973}>", "<name:Ahn professor female age=61 subject=\computer\math_{20092931}>"]

def get_identity(code):
    print([row.split(' ')[1] for row in current_list if code in row][0])


get_identity("{20092973}")

regular expression is good ,but for me, a rookie, regular expression is another big problem...