问题
I'm trying to use a batch file to confirm a network connection using ping. I want to do batch run and then print if the ping was successful or not. The problem is that it always displays 'failure' when run as a batch. Here is the code:
@echo off
cls
ping racer | find "Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),"
if not errorlevel 1 set error=success
if errorlevel 1 set error=failure
cls
echo Result: %error%
pause
'racer' is the name of my computer. I'm having my computer ping itself so I can eliminate the variable of a poor connection. As I said before, the batch always results in failure. Oddly enough, the program works fine if I copy the code into the command prompt. Does anyone know why the program works fine in the command prompt but doesn't work as a batch? Thanks
回答1:
I 'm not exactly sure what the interaction between FIND and setting the error level is, but you can do this quite easily:
@echo off
for /f %%i in ('ping racer ^| find /c "(0%% loss)"') do SET MATCHES=%%i
echo %MATCHES%
This prints 0 if the ping failed, 1 if it succeeded. I made it look for just "0% loss" (not specifically 4 pings) so that the number of pings can be customized.
The percent sign has been doubled so that it's not mistaken for a variable that should be substituted.
The FOR trick serves simply to set the output of a command as the value of an environment variable.
回答2:
A more reliable ping error checking method:
@echo off
set "host=192.168.1.1"
ping -n 1 "%host%" | findstr /r /c:"[0-9] *ms"
if %errorlevel% == 0 (
echo Success.
) else (
echo FAILURE.
)
This works by checking whether a string such as 69 ms or 314ms is printed by ping.
(Translated versions of Windows may print 42 ms (with the space), hence we check for that.)
Reason:
Other proposals, such as matching time= or TTL are not as reliable, because pinging IPv6 addresses doesn't show TTL (at least not on my Windows 7 machine) and translated versions of Windows may show a translated version of the string time=. Also, not only may time= be translated, but sometimes it may be time< rather than time=, as in the case of time<1ms.
回答3:
If you were to
echo "Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),"
you would see the % is stripped. You need to escape it as % has a special meaning within a batch file:
"Packets: Sent = 4, Received = 4, Lost = 0 (0%% loss),"
However its simpler to use TTL as the indication of success;
.. | find "TTL"
回答4:
Testing for 0% loss may give a false positive, in this scenario: Let's say you normally have a network drive on some_IP-address, and you want to find out whether or not it's on.
If that drive is off, and you ping some_IP-address, the IP address from which you ping, will respond:
Answer from your_own_IP-address: target host not reachable
... 0% loss
You might be better off using if exist or if not exist on that network location.
回答5:
The most simple solution to this I can think of:
set error=failure
ping racer -n 1 -w 100>nul 2>&1 && set error=success
Of course, -w needs to be adjusted if on a slow link (100ms might be too short over Dialup ;-))
regards
回答6:
Another variation without using any variable
ping racer -n 1 -w 100>nul || goto :pingerror
...
:pingerror
echo Host down
goto eof
:eof
exit /b
回答7:
Yes ping fails to return the correct errorlevel. To check the network connection and the computer I used "net view computername" then checked %errorlevel% - simple and easy
回答8:
ping 198.168.57.98 && echo Success || echo failed
回答9:
First of all
>@echo off
>for /f %%i in ('ping racer ^| find /c "(0%% loss)"') do SET MATCHES=%%i
>echo %MATCHES%
Does not work. If it won't fail, it will detect 0%, because it has 0%. If it fails, does not work either, because it will have 100% loss, which means, it found the 0% loss part behind the 10 10(0% loss)
Have it detect for 100% loss like so:
>for /f %%i in ('ping -n 1 -l 1 %pc% ^| find /c "(100%% loss)"') do SET check=%%i
Errorlevel might be a bit messed up, but it works like a charm:
>if '%check%'=='1' goto fail
>if '%check%'=='0' echo %pc% is online.&goto starting
1 means it failed 0 means it succeeded
In my script is use links. Goto fail will go to :fail in my script which will message me that %pc% (which I'll have the user input in the beginning) is offline and will go for another run.
>:fail
>color 0c
>title %pc% is offline
>echo %pc% is offline
>PING -n 6 127.0.0.1>nul
>goto choice
I hope this helps.
回答10:
ping has an errorlevel output value. Success is 0, failure is 1. Just do this:
C:\>ping 4.2.2.2
Pinging 4.2.2.2 with 32 bytes of data:
Reply from 4.2.2.2: bytes=32 time=28ms TTL=57
Reply from 4.2.2.2: bytes=32 time=29ms TTL=57
Reply from 4.2.2.2: bytes=32 time=30ms TTL=57
Reply from 4.2.2.2: bytes=32 time=29ms TTL=57
Ping statistics for 4.2.2.2:
Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 28ms, Maximum = 30ms, Average = 29ms
C:\>echo %errorlevel%
0
C:\>ping foo.bar
Ping request could not find host foo.bar. Please check the name and try again.
C:\>echo %errorlevel%
1
As you can see there is no need for all this scripting overkill.
回答11:
Based on Alex K's note, this works for me on Windows 7:
@echo off
setlocal enableextensions enabledelayedexpansion
for /f %%i in (PCS.TXT) do (
SET bHOSTUP=0
ping -n 2 %%i |find "TTL=" > NUL && SET bHOSTUP=1
IF !bHOSTUP! equ 1 (
CALL :HOSTUP %%i
) else (
CALL :HOSTDOWN %%i
)
)
GOTO EOF
:HOSTUP
echo Host UP %1
GOTO EOF
:HOSTDOWN
echo Host DOWN %1
GOTO EOF
:EOF
exit /B
回答12:
I liked the concept of the FIND in the ping results but why not just FIND the Reply from the Address being pinged?
In the example below I enter an IP address as a variable, PING that IP, then look for that variable in the reply string, using the FIND Command. If the Reply String contains anything other than the correct IP it reports failure.
If you want you can just read the value of ERRORLEVEL from the FIND. That will give you a reliable value to work with.
@echo off
Set /P IPAdd=Enter Address:
cls
ping %IPAdd% | find "Reply from %IPAdd%:"
if not errorlevel 1 set error=success
if errorlevel 1 set error=failure
cls
echo Result: %error%
pause
回答13:
I needed to reset a wifi connection because it has issues. This was my quick solution.
@echo off
Rem Microsoft Windows 10 ping test to gateway.
Rem Run batch file from an administrative command prompt.
cls
:starting
Rem Send one ping to the gateway. Write the results to a file.
ping 192.168.1.1 -n 1 > pingtest.txt
Rem Search for unreachable in the file.
c:\windows\system32\findstr.exe "unreachable" pingtest.txt
Rem errorlevel 0 reset the adapter if 1 then wait 10 minutes and test again
if %errorlevel%==1 goto waiting
Rem unreachable was found reset the adapter.
Rem write the date and time the reset was done.
echo Reset date: %date% time: %time% >> resettimes.txt
Rem issue netsh interface show interface to find your adapter's name to reset
Rem my adapter is "wi-fi"
netsh interface set interface "wi-fi" disable
timeout /t 5
netsh interface set interface "wi-fi" enable
:waiting
echo "It is online waiting 10 minutes"
timeout /t 600
goto starting
来源：https://stackoverflow.com/questions/9329749/batch-errorlevel-ping-response