python 如何得到匹配到string的行

tianting002

文件名:change.log
我想匹配到error并返回行.

类似于grep error change.log

用python如何实现？




change.log 文件内容

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用perl实现如下：
#!/usr/bin/perl -w

open(F1,"change.log"||die "Cannot open change.log!";

my @grp=<F1>;

foreach my $va(@grp) {
        #print $va;

if ($va=~/error/i) {

        print "$va\n";
}
}


python怎么匹配？

anonymous0502

1. print ''.join([x for x in open('change.log').readlines() if x.find('error')!=-1])

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或者用正则表达式re

sunny7476

楼上是好人啊！

tianting002

anonymous0502 发表于 2012-04-26 15:30
或者用正则表达式re

!=-1 不等于-1是什么意思？

另外用re怎么实现？

ilikeqdi

1. >>> x='error xxxx'
   
2. >>> x.find('error')
   
3. 0
   
4. >>> x.find('abc')
   
5. -1
   

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自己试一下不就知道了

ilikeqdi

1. print ''.join([x for x in open('change.log').readlines() if re.search('error',x))

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借用一下,应该是这样,没测试

tianting002

回复 5# ilikeqdi


谢谢。

print ''.join([x for x in open('change.log').readlines() if x.find('error')!=-1])

这句如何忽略大小写error?


   

ilikeqdi

1. print ''.join([x for x in open('change.log').readlines() if re.search('error',x,re.I))

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忽略大小写

tianting002

回复 8# ilikeqdi


    string.find()能忽略大小写吗？ 不用正则。

ilikeqdi

好像是不行