建站
咨詢
售后
建站咨詢
新聞中心
這里有您想知道的互聯(lián)網(wǎng)營銷解決方案
批處理set命令
批處理中的set命令用于設置環(huán)境變量。
批處理BAT腳本是Windows操作系統(tǒng)中一種非常實用的腳本語言，它可以幫助我們自動化完成一些重復性的工作，在批處理腳本中，set命令是一個非常重要的命令，它可以用來設置或顯示環(huán)境變量，本文將對set命令的使用進行詳細的介紹。
set命令的基本用法
1、設置環(huán)境變量
使用set命令可以設置環(huán)境變量，語法如下：
set 變量名=變量值
我們可以設置一個名為PATH的環(huán)境變量，用于存儲程序的搜索路徑：
set PATH=C:Windows;C:Program FilesJava;C:Program FilesPython
2、顯示環(huán)境變量
使用set命令可以顯示當前已經(jīng)設置的所有環(huán)境變量，語法如下：
set
我們可以查看當前已經(jīng)設置的所有環(huán)境變量：
set
set命令的常用選項
1、/a：追加環(huán)境變量，而不是覆蓋原有的值，如果環(huán)境變量已經(jīng)存在，則在其值的后面追加新的值；如果環(huán)境變量不存在，則直接設置新的值。
我們可以追加一個名為JAVA_HOME的環(huán)境變量：
set JAVA_HOME=C:Program FilesJava /a
2、/p：提示用戶輸入要設置的值，這對于需要用戶輸入的環(huán)境變量非常有用。
我們可以提示用戶輸入一個名為USERNAME的環(huán)境變量：
set /p USERNAME=請輸入用戶名：
3、/x：刪除指定的環(huán)境變量，如果環(huán)境變量不存在，則不執(zhí)行任何操作。
我們可以刪除一個名為TEST的環(huán)境變量：
set TEST= /x
set命令的注意事項
1、set命令設置的環(huán)境變量僅對當前的批處理腳本有效，當腳本執(zhí)行完畢后，設置的環(huán)境變量會自動失效，如果需要永久設置環(huán)境變量，可以將set命令添加到系統(tǒng)的環(huán)境變量配置文件中（如Windows系統(tǒng)中的system32driversetchosts文件）。
2、set命令設置的環(huán)境變量是以字符串的形式存儲的，即使我們需要設置的是數(shù)字或其他類型的值，也需要將其轉換為字符串，我們可以將一個數(shù)字轉換為字符串并設置為環(huán)境變量：
set NUMBER=12345 /a echo %NUMBER% > temp.txt && type temp.txt | findstr /r "^[0-9]*$" > nul && set /p NUMBER=> num.txt && for /f "delims=" %%i in (num.txt) do set NUMBER=%%i && del num.txt && echo %NUMBER%:%NUMBER% >> num.txt && for /f "delims=" %%i in (num.txt) do set NUMBER=%%i && del num.txt && echo %NUMBER%:%NUMBER% >> num.txt && for /f "delims=" %%i in (num.txt) do set NUMBER=%%i && del num.txt && echo %NUMBER%:%NUMBER% >> num.txt && for /f "delims=" %%i in (num.txt) do set NUMBER=%%i && del num.txt && echo %NUMBER%:%NUMBER% >> num.txt && for /f "delims=" %%i in (num.txt) do set NUMBER=%%i && del num.txt && echo %NUMBER%:%NUMBER% >> num.txt && for /f "delims=" %%i in (num.txt) do set NUMBER=%%i && del num.txt && echo %NUMBER%:%NUMBER% >> num.txt && for /f "delims=" %%i in (num.txt) do set NUMBER=%%i && del num.txt && echo %NUMBER%:%NUMBER% >> num.txt && for /f "delims=" %%i in (num.txt) do set NUMBER=%%i && del num.txt && echo %NUMBER%:%NUMBER% >> num.txt && for /f "delims=" %%i in (num.txt) do set NUMBER=%%i && del num.txt && echo %NUMBER%:%NUMBER% >> num.txt && for /f "delims=" %%i in (num.txt) do set NUMBER=%%i && del num.txt && echo %NUMBER%:%NUMBER% >> num.txt && for /f "delims=" %%i in (num.txt) do set NUMBER=%%i && del num.txt && echo %NUMBER%:%NUMBER% >> num.txt && for /f "delims=" %%i in (num.txt) do set NUMBER=%%i && del num.txt && echo %NUMBER%:%NUMBER% >> num.txt && for /f "delims=" %%i in (num.txt) do set NUMBER=%%i && del num.txt && echo %NUMBER%:%NUMBER% >> num.txt && for /f "delims=" %%i in (num.txt) do set NUMBER=%%i && del num.txt && echo %NUMBER%:%NUMBER% >> num.txt && for /f "delims=" %%i in (num.txt) do set NUMBER=%%i && del num.txt && echo %NUMBER%:%NUMTALBREAK>12345:12345>> num.txt && for /f "delims=" %i in (num.txt) do set NUMBER=!i! & goto endnum & endlocal & goto endbatch & endlocal & goto endbatch & endlocal & goto endbatch & endlocal & goto endbatch & endlocal & goto endbatch & endlocal & goto endbatch & endlocal & goto endbatch & endlocal & goto endbatch & endlocal & goto endbatch & endlocal & goto endbatch & endlocal & goto endbatch & endlocal & goto endbatch & endlocal & goto endbatch & endlocal & goto endbatch & endlocal & goto endbatch & endlocal & goto endbatch & endlocal & goto endbatch & endlocal & goto endbatch & endlocal & goto endbatch & endlocal & goto endbatch & endlocal & goto endbatch & endlocal & goto endbatch & endlocal & goto endbatch & endlocal & goto endbatch & endlocal & goto endbatch & endlocal & goto endbatch & endlocal & goto endbatch & endlocal & goto endbatch & endlocal & goto endbatch & endlocal & goto endbatch & endlocal & goto endbatch & endlocal & goto endbatch & endlocal & goto endbatch & endlocal & goto endbatch & endlocal & goto endbatch & endlocal & goto endbatch & endlocal & goto endbatch &endnum:&for /f "tokens=*" %j in ('dir /b C:') do if not "%~j" == "num.txt" if not "%~j" == "nul" if not "%~j" == "temp.txt" if not "%~j" == "%~nx0" if not "%~j" == "%~dp0" if not "%~j" == "%~nx0" if not "%~j" == "%~dp0" if not "%~j" == "%~nx0" if not "%~j" == "%~dp0" if not "%~j" == "%~nx0" if not "%~j" == "%~dp0" if not "%~j" == "%~nx0" if not "%~j" == "%~dp0" if not "%~j" == "%~nx0" if not "%~j" == "%~dp0" if not "%~j" == "%~nx0" if not "%~j" == "%~dp0" if not "%~j" == "%~nx0" if not "%~j" == "%~dp0" if not "%~j" == "%~nx0" if not "%~j" == "%~dp0" if not "%~j" == "%~nx0" if not "%~j" == "%~dp0" if not "%~j" == "%~nx0" if not "%~j" == "%~dp0" if not "%~j" == "%~nx0" if not "%~j" == "%~dp0" if not "%~j" == "%~nx0" if not "%~j" == "%~dp0ifnot "%~j" == "%~nx0ifnot "%~j" == "%~dp0ifnot "%~j" == apendnumifnot ""==12345goto startnum&goto startnum&goto start
新聞名稱：批處理set命令
新聞來源：http://www.dlmjj.cn/article/dpghopj.html
