As the question says..
For example set /p a=Number or letter
How to write it?? (It's a randomly entered number)
For example set /p a=Number or letter
How to write it?? (It's a randomly entered number)
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中国DOS联盟论坛 » DOS批处理 & 脚本技术（批处理室） » How to judge whether the input is a number or a letter in batch processing?
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Posted 2006-11-24 07:48 · 中国 湖南 长沙 电信
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Posted 2006-11-24 08:38 · 中国 广东 电信
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I thought that using the regular expression of findstr would easily complete the task, but unexpectedly there was still a bug: when the last character of the string is the escape character ^, an incorrect judgment result will appear:
@echo off
:begin
cls
set input=
set /p input= Please enter a string:
if "%input%"=="" goto begin
echo.
echo %input%|findstr "^*$">nul && echo The string you entered is purely numeric||(
echo %input%|findstr "^*$">nul && echo The string you entered is purely alphabetic||echo The string you entered is neither purely numeric nor purely alphabetic
)
echo.
pause
goto begin
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| Rater | Score | Time |
|---|---|---|
| redtek | +3 | 2006-11-24 11:23 |
尺有所短，寸有所长，学好CMD没商量。
考虑问题复杂化，解决问题简洁化。
考虑问题复杂化，解决问题简洁化。
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Posted 2006-11-24 08:52 · 中国 湖南 长沙 电信
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Thank you, moderator大哥. I just tried it and it works very well...
I just don't know what the code means, heh heh...
Can you take some time to explain it... Thanks.
I just don't know what the code means, heh heh...
Can you take some time to explain it... Thanks.
Floor 4
Posted 2006-11-24 11:28 · 中国 北京 东城区 联通
Wonderful~~Learned from the moderator~~ :))))
Redtek，一个永远在网上流浪的人……
_.,-*~'`^`'~*-,.__.,-*~'`^`'~*-,._,_.,-*~'`^`'~*-,._,_.,-*~'`^`'~*-,._
_.,-*~'`^`'~*-,.__.,-*~'`^`'~*-,._,_.,-*~'`^`'~*-,._,_.,-*~'`^`'~*-,._
Floor 5
Posted 2006-11-24 12:52 · 中国 浙江 温州 电信
The simplest way, compare variable with number. If the variable is a number, the comparison will succeed. If the variable is not a number, the comparison fails.
if %a% GTR 0 echo %a% is a number
if %a% GTR 0 echo %a% is a number
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Posted 2006-11-24 14:01 · 中国 湖南 长沙 电信
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zerocq Please write out all of them, okay??
I'm a noob, only this sentence I don't understand~~
I'm a noob, only this sentence I don't understand~~
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Posted 2006-11-24 22:19 · 中国 广东 清远 联通
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From 湖南==》广东
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Direct comparison with numbers can cause errors! Test code:
@echo off
set /p num=Please enter a number:
if %num% geq 1 (echo YES) else echo NO
pause>nul
When you enter 10a, it returns YES!
I think there are two solutions:
1. findstr + regular expression, the previous moderator has used it;
2. Use the particularity of set /a:
For example: set /a num=10a, then num cannot be defined correctly. If it starts with a letter, the return result of num is 0. If it is pure numbers, it returns the original number. Using this feature, it can be used to roughly detect the input situation.
@echo off
set /p num=Please enter a number:
if %num% geq 1 (echo YES) else echo NO
pause>nul
When you enter 10a, it returns YES!
I think there are two solutions:
1. findstr + regular expression, the previous moderator has used it;
2. Use the particularity of set /a:
For example: set /a num=10a, then num cannot be defined correctly. If it starts with a letter, the return result of num is 0. If it is pure numbers, it returns the original number. Using this feature, it can be used to roughly detect the input situation.
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| redtek | +3 | 2006-11-24 22:27 |
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