两个字符串之间的正则表达式文本

Question

I am trying to extract data fields from PDF texts using regex.

The text is:

"SAMPLE EXPERIAN CUSTOMER\\n2288150 - EXPERIAN SAMPLE REPORTS\\nData Dictionary Report\\nFiltered By:\\nCustom Selection\\nMarketing Element:\\nPage 1 of 284\\n2014-11-11 21:52:01 PM\\nExperian and the marks used herein are service marks or registered trademarks of Experian.\\n© Experian 2014 All rights reserved. Confidential and proprietary.\\n**Data Dictionary**\\nDate of Birth is acquired from public and proprietary files. These sources provide, at a minimum, the year of birth; the month is provided where available. Exact date of birth at various levels of detail is available for \\n\\n\\n\\n\\n\\nNOTE: Records coded with DOB are exclusive of Estimated Age (101E)\\n**Element Number**\\n0100\\nDescription\\nDate Of Birth / Exact Age\\n**Data Dictionary**\\n\\n\\n\\n\\n\\n\\n\\n\\n\\n\\nFiller, three bytes\\n**Element Number**\\n0000\\n**Description**\\nEnhancement Mandatory Append\\n**Data Dictionary**\\n\\n\\nWhen there is insufficient data to match a customer's record to our enrichment master for estimated age, a median estimated age based on the ages of all other adult individuals in the same ZIP+4 area is provided. \\n\\n\\n\\n\\n\\n\\n00 = Unknown\\n**Element Number**\\n0101E\\n**Description**\\nEstimated Age\\n"

The field names are in bold. The texts between field names are the field values.

The first time I tried to extract the 'Description' field using the following regex:

pattern = re.compile('\nDescription\n(.*?)\nData Dictionary\n')
re.findall(pattern,text)

The results are correct:

['Date Of Birth / Exact Age', 'Enhancement Mandatory Append']

But using the same idea to extract 'Data Dictionary' Field gives the empty result:

pattern = re.compile('\nData Dictionary\n(.*?)\nElement Number\n')
re.findall(pattern,text)

Results:

[]

Any idea why?

Answer 1

. doesn't match newlines by default. Try:

pattern = re.compile('\nData Dictionary\n(.*?)\nElement Number\n', flags=re.DOTALL)
re.findall(pattern,text)

Notice how I passed re.DOTALL as the flags argument to re.compile .

Answer 2

Try using the flag re.MULTILINE in your regex:

pattern = re.compile('\nData Dictionary\n(.*?)\nElement Number\n', re.MULTILINE)
re.findall(pattern,text)