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    批处理提取不同行上的内容的代码

    作者:admin 时间:2021-02-19 15:41

    for instance:-

    for /f "delims=" %%a in (input.txt) do ...

    for /f "delims=" %%a in ('type input.txt') do ...

    for /f "delims=" %%a in ('more ^< input.txt') do ...

    However, only the last method (using the more command) will give consistent results across Windows NT, 2000, XP and 2003. The first method does not recognise unicode files. Also, the usebackq switch must be used if the input filename contains spaces. The second method, using the type command, also fails to recognise unicode files on Windows 2000, XP and 2003 if the input file does not begin with a bit order mark (BOM).

    In all the examples, assume the contents of of the file numbers.txt to be:-

    one
    two
    three
    four
    five
    six
    seven
    eight
    nine
    ten

    Displaying the first line

    This example prints one.

    @echo off & setlocal ENABLEEXTENSIONS
    set "first="
    for /f "delims=" %%a in ('more ^< numbers.txt') do (
    if not defined first set first=%%a
    )
    echo/%first%

    Displaying the first X lines

    This example prints one, two and three.

    @echo off & setlocal ENABLEEXTENSIONS
    set "lines=3"
    set i=-1
    set "ok="
    for /f "delims=" %%a in ('more ^< numbers.txt') do (
    set/a i+=1 & for /f %%z in ('echo/%%i%%') do (
    if "%%z"=="%lines%" set ok=1
    )
    if not defined ok echo/%%a
    )

    Displaying the last line

    This example prints ten.

    @echo off & setlocal ENABLEEXTENSIONS
    for /f "delims=" %%a in ('more ^< numbers.txt') do set "last=%%a"
    echo/%last%

    Displaying the last X lines

    This example prints nine and ten.

    @echo off & setlocal ENABLEEXTENSIONS
    set "lines=2"
    for /f %%a in ('find/c /v "" ^< numbers.txt') do set/a skip=%%a-lines
    for /f "delims=" %%a in ('more/e +%skip% ^< numbers.txt') do (
    echo/%%a
    )

    Displaying the Nth line

    This example prints three. Note that instead of using the more command's /e switch, the skip option could have been used with the for /f command, however, this fails is it is set to any number less than one.

    @echo off & setlocal ENABLEEXTENSIONS
    set LineNo=3
    set "line="
    set/a LineNo-=1
    for /f "delims=" %%a in ('more/e +%LineNo% ^< numbers.txt') do (
    if not defined line set "line=%%a"
    )
    echo/%line%

    Displaying the Nth line plus X number of lines

    This example prints five and six.

    @echo off & setlocal ENABLEEXTENSIONS
    set start=5
    set "lines=2"
    set/a i=-1,start-=1
    set "ok="
    for /f "delims=" %%a in ('more/e +%start% ^< numbers.txt') do (
    set/a i+=1 & for /f %%z in ('echo/%%i%%') do (
    if "%%z"=="%lines%" set ok=1
    )
    if not defined ok echo/%%a
    )
    js
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