How to extract characters between the delimiters using sed?

问题

I have just started learning sed. I want to extract and print the characters between the > and < delimiters. Here the text in my data file:

<span id="ctl00_ContentPlaceHolder1_lblRollNo">12029</span>

   <br /><b>Engineering & IT/Computer Science</b><br />

        <div id="ctl00_ContentPlaceHolder1_divEngITMerit">

                        <span id="ctl00_ContentPlaceHolder1_lblEngITSelListNo">3rd Provisional Selection List</span>

                <tr><td style='width: 200px' class='TblTRData'>IT/Computer Science/Software</td><td style='width: 150px'class='TblTRData'>7 (out of 471)</td><td style='width: 325px'class='TblTRData'>Selected in MS COMPUTER SCIENCE</td></tr>

                                Name:

                                <span id="ctl00_ContentPlaceHolder1_lblName">SIDRA SHAHID</span>

                                Father Name:

                                <span id="ctl00_ContentPlaceHolder1_lblFatherName">SHAHID RAFEEQ AHMAD</span>

I have written the command:

sed -n -e '/^[^>]*>\([^<]*\)<.*/s//\1/p' myfile.txt

The problem is that it is returning the text between some of the > <. For example, it prints 12029, but not Selected in Selected in MS COMPUTER SCIENCE. What am I doing wrong?

回答1:

If you need to extract only strings between tags, this means you need to delete tags leaving strings between them untouched. Right?

sed 's/<[^>]*>//g'

It substitutes (all occurrences) of tag ( "<" everything upon next ">" ) with empty string (nothing). Text will remain.

回答2:

In sed, the s command has a g flag to operate on all pattern occurrences on a same line.

s/>\([^<]*\)</\1/pg

might suffice.

来源：https://stackoverflow.com/questions/7684729/how-to-extract-characters-between-the-delimiters-using-sed

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Linux

scripting

sed