方法/步骤 1 if命令3种基本用法，可以通在cmd中使用if /?来查看到。IF [NOT] ERRORLEVEL number comman IF [NOT] string1==string2 commandIF [NOT] EXIST filename command 2 if 条件表达式 (语句1) else (语句2)，条件表达式成立执行语句1，否则，将执行语句2；if语句几个常用的用法，判断驱动器、文件...
方法/步骤 1 if语句用法，判断判断驱动器，文件或文件夹是否存在if exist filename commandif exist filename 是表示：存在 filename意思。判断盘符是否存在的简单例子if exist "e:" (echo e盘存在) else echo e盘不存在。2 @echo offdir /a-d d:\123.bat >nul 2>nulif %errorlevel%==0 (echo 123....
IF [/I] string1 compare-op string2 command IF CMDEXTVERSION number command IF DEFINED variable command 数字比较 EQU - 等于 NEQ 不等于 LSS - 小于 LEQ - 小于或等于 GTR - 大于 GEQ - 大于或等于 3)Else和 )同一行 IF EXIST filename (del filename.) ELSE echo filename Missing 或 IF EXIST...
usedtomake conditionaljudgments.Ifacertainconditionismet,the followingcommandisexecuted. Mainlyusedtodeterminewhetherthe1andtwostringsareequal; 2,twovaluesaregreaterthan,lessthan,equalto,andthen executethecorrespondingcommand. Ofcourse,therearespecialuses,suchascombining errorlevel:iferrorlevel1,echo,error Or...
:CHECKACCOUNT if /I "%user%"=="insertusername" GOTO ACCOUNT GOTO CHECKPASSACCT :CHECKPASSACCT if /I "%pass%"=="insertpassword" GOTO ACCOUNT GOTO COUNTER不需要 ELSE语句。由于 IF块将跳转到其他位置，将第二个 GOTO放在下一行或 ELSE块中应该是等效的。 此外，在定义 GOTO目标时需要前导冒号，但...
Performs conditional processing in batch programs. For examples of how to use this command, see Examples. Syntax Copy if [not] ERRORLEVEL <Number> <Command> [else <Expression>] if [not] <String1>==<String2> <Command> [else <Expression>] if [not] exist <FileName> <Command> [else <...
Performs conditional processing in batch programs. Syntax Copy if [not] ERRORLEVEL <number> <command> [else <expression>] if [not] <string1>==<string2> <command> [else <expression>] if [not] exist <filename> <command> [else <expression>] If command extensions are enabled, use the ...
Performs conditional processing in batch programs. Syntax if [not] errorlevel Number Command [else Expression] if [not] String1**==**String2 Command [else Expression] if [not] exist FileName Command [else Expression] If command extensions are enabled, use the following syntax: if [/i] Strin...
<c:choose> <c:when test="${requestScope.newFlag== '1' || requestScope.newFlag== '2' ...
The following example show how the ‘if’ statement can be used to check for the values of the command line arguments.Example@echo off echo %1 echo %2 echo %3 if %1%==1 (echo "The value is 1") else (echo "Unknown value") if %2%==2 (echo "The value is 2") else (echo "...