Batch - If, ElseIf, Else

问题

Whats wrong with this code?

IF "%language%" == "de" (
    goto languageDE
) ELSE (
    IF "%language%" == "en" (
    goto languageEN
) ELSE (
    echo Not found.
)

I'm not really good in Batch..

回答1:

@echo off
title Test

echo Select a language. (de/en)
set /p language=

IF /i "%language%"=="de" goto languageDE
IF /i "%language%"=="en" goto languageEN

echo Not found.
goto commonexit

:languageDE
echo German
goto commonexit

:languageEN
echo English
goto commonexit

:commonexit
pause

The point is that batch simply continues through instructions, line by line until it reaches a goto, exit or end-of-file. It has no concept of sections to control flow.

Hence, entering de would jump to :languagede then simply continue executing instructions until the file ends, showing de then en then not found.

回答2:

@echo off

set "language=de"

IF "%language%" == "de" (
    goto languageDE
) ELSE (
    IF "%language%" == "en" (
        goto languageEN
    ) ELSE (
    echo Not found.
    )
)

:languageEN
:languageDE

echo %language%

This works , but not sure how your language variable is defined.Does it have spaces in its definition.

回答3:

batchfiles perform simple string substitution with variables. so, a simple

goto :language%language%
echo notfound
...

does this without any need for if.

回答4:

Recommendation. Do not use user-added REM statements to block batch steps. Use conditional GOTO instead. That way you can predefine and test the steps and options. The users also get much simpler changes and better confidence.

@Echo on
rem Using flags to control command execution

SET ExecuteSection1=0
SET ExecuteSection2=1

@echo off

IF %ExecuteSection1%==0 GOTO EndSection1
ECHO Section 1 Here

:EndSection1

IF %ExecuteSection2%==0 GOTO EndSection2
ECHO Section 2 Here
:EndSection2

回答5:

@echo off
color 0a
set /p language=
if %language% == DE (
    goto LGDE
) else (
    if %language% == EN (
    goto LGEN
    ) else (
    echo N/A
)

:LGDE
(code)
:LGEN
(code)

来源：https://stackoverflow.com/questions/25384358/batch-if-elseif-else

标签

batch-file

if-statement