- 论坛徽章:
- 33
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整理一下格式
1.得到字符串长度
方法一:
$echo ${#variable}
- zhyfly: ~$ x="this is a test"
- zhyfly: ~$ echo ${#x}
- 14
$expr length "$variable"
- zhyfly: ~$ x="this is a test"
- zhyfly: ~$ expr length "$x"
- 14
$expr "$variable" : ".*"
- zhyfly: ~$ x="this is a test"
- zhyfly: ~$ expr "$x" : ".*"
- 14
方法:
$expr index "$variable" "substring"
- zhyfly: ~$ x="this is a test"
- zhyfly: ~$ expr index "$x" "is"
- 3
- zhyfly: ~$ expr index "$x" "t"
- 1
3.得到字符串子字符串
方法一:
$echo ${variable:position:length}
- zhyfly: ~$ x="this is a test"
- zhyfly: ~$ echo ${x:1:5}
- his i
$expr substr "$variable" startposition length
- zhyfly: ~$ x="this is a test"
- zhyfly: ~$ expr substr "$x" 1 5
- this
4.匹配正则表达式之匹配长度
方法:
$expr match "$x" "string"
- zhyfly: ~$ x="this is a test"
- zhyfly: ~$ expr match "$x" "his"
- 0
- zhyfly: ~$ expr match "$x" "this"
- 4
- zhyfly: ~$ expr match "$x" "."
- 1
方法:
$echo ${variable#startletter*endletter} # #表示掐头,因为键盘上#在$前面,一个表示最小匹配
$echo ${variable##tartletter*endletter} 两个表示最大匹配
$echo ${variable%startletter*endletter} # %表示去尾,因为键盘上%在$后面,一个表示最小匹配
$echo ${variable%%startletter*endletter} 两个表示最大匹配
- zhyfly: ~$ x="this is a test"
- zhyfly: ~$ echo ${x#t}
- his is a test
- zhyfly: ~$ echo ${x#t*h}
- is is a test
- zhyfly: ~$ echo ${x#t*s}
- is a test
- zhyfly: ~$ echo ${x##t*s}
- t
- zhyfly: ~$ echo ${x%t}
- this is a tes
- zhyfly: ~$ echo ${x%s*t}
- this is a te
- zhyfly: ~$ echo ${x%e*t}
- this is a t
- zhyfly: ~$ echo ${x%%i*t}
- th
方法:
$echo ${variable/oldletter/newletter} #替换一个
$echo ${variable//oldletter/newletter} #替换所有
- zhyfly: ~$ x="this is a test"
- zhyfly: ~$ echo ${x/i/m}
- thms is a test
- zhyfly: ~$ echo ${x//i/m}
- thms ms a test
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发表于 2007-01-04 10:28
发表于 2013-05-23 10:31
