shell腳本中變量的第一個字符是否為大寫？

Question

我有一個shell腳本，可以啟動模塊的單元測試。 我需要全部小寫的模塊名稱和第一個字符大寫。 到目前為止，我一直在這樣做：

#!/bin/sh -x                                                                                                                                                                          
# z.B. getbrowser                                                                                                                                                                     
strModuleToTest=$1

# g                                                                                                                                                                                   
strModuleToTestUppercaseFirstletter=${strModuleToTest:0:1}
# etbrowser                                                                                                                                                                           
strModuleToTestUppercaseLastletters=${strModuleToTest:1}

# g -> G                                                                                                                                                                              
strModuleToTestUppercaseFirstletter="${strModuleToTestUppercaseFirstletter/a/A}"
strModuleToTestUppercaseFirstletter="${strModuleToTestUppercaseFirstletter/b/B}"
strModuleToTestUppercaseFirstletter="${strModuleToTestUppercaseFirstletter/c/C}"
strModuleToTestUppercaseFirstletter="${strModuleToTestUppercaseFirstletter/d/D}"
strModuleToTestUppercaseFirstletter="${strModuleToTestUppercaseFirstletter/e/E}"
strModuleToTestUppercaseFirstletter="${strModuleToTestUppercaseFirstletter/f/F}"
strModuleToTestUppercaseFirstletter="${strModuleToTestUppercaseFirstletter/g/G}"
strModuleToTestUppercaseFirstletter="${strModuleToTestUppercaseFirstletter/h/H}"
strModuleToTestUppercaseFirstletter="${strModuleToTestUppercaseFirstletter/i/I}"
strModuleToTestUppercaseFirstletter="${strModuleToTestUppercaseFirstletter/j/J}"
strModuleToTestUppercaseFirstletter="${strModuleToTestUppercaseFirstletter/k/K}"
strModuleToTestUppercaseFirstletter="${strModuleToTestUppercaseFirstletter/l/L}"
strModuleToTestUppercaseFirstletter="${strModuleToTestUppercaseFirstletter/m/M}"
strModuleToTestUppercaseFirstletter="${strModuleToTestUppercaseFirstletter/n/N}"
strModuleToTestUppercaseFirstletter="${strModuleToTestUppercaseFirstletter/o/O}"
strModuleToTestUppercaseFirstletter="${strModuleToTestUppercaseFirstletter/p/P}"
strModuleToTestUppercaseFirstletter="${strModuleToTestUppercaseFirstletter/q/Q}"
strModuleToTestUppercaseFirstletter="${strModuleToTestUppercaseFirstletter/r/R}"
strModuleToTestUppercaseFirstletter="${strModuleToTestUppercaseFirstletter/s/S}"
strModuleToTestUppercaseFirstletter="${strModuleToTestUppercaseFirstletter/t/T}"
strModuleToTestUppercaseFirstletter="${strModuleToTestUppercaseFirstletter/u/U}"
strModuleToTestUppercaseFirstletter="${strModuleToTestUppercaseFirstletter/v/V}"
strModuleToTestUppercaseFirstletter="${strModuleToTestUppercaseFirstletter/w/W}"
strModuleToTestUppercaseFirstletter="${strModuleToTestUppercaseFirstletter/x/X}"
strModuleToTestUppercaseFirstletter="${strModuleToTestUppercaseFirstletter/y/Y}"
strModuleToTestUppercaseFirstletter="${strModuleToTestUppercaseFirstletter/z/Z}"

# Getbrowser
strModuleToTestUppercase=$strModuleToTestUppercaseFirstletter""$strModuleToTestUppercaseLastletters

設置$ strModuleToTestUppercase更簡單的方法是什么？ 我試過了

strModuleToTestUppercase="${strModuleToTest[@]^}"

要么

strModuleToTestUppercasesed="sed 's/\<./\u&/g' $strModuleToTest"

但沒有成功。

Answer 1

如果：

s=somemodule

用bash v4 +

echo ${s^}

這應該適用於較舊的bash版本（來自Glenn）：

echo $(tr a-z A-Z <<< ${s:0:1})${s:1}"

用zsh

echo ${(C)s}

用灰和coreutils

echo $(echo $s | cut -c1 | tr a-z A-Z)$(echo $s | cut -c2-)

與GNU sed

echo $s | sed 's/./\U&/'

與BSD sed

echo $s | sed '
  h;
  y/quvwxzdermatoglyphicsbfjkn/QUVWXZDERMATOGLYPHICSBFJKN/;
  G;
  s/\(.\)[^\n]*\n.\(.*\)/\1\2/;
'

用awk

echo $s | awk '{ print toupper(substr($0, 1, 1)) substr($0, 2) }'

與perl

echo $s | perl -nE 'say ucfirst'

用python

echo $s | python -c 'import sys; print sys.stdin.readline().rstrip().capitalize()'

用紅寶石

echo $s | ruby -e 'puts ARGF.read.capitalize'

在所有情況下輸出

Somemodule

Answer 2

你可以用

strModuleToTestUpper=`sed 's/\(.\)/\U\1/' <<< "$strModuleToTest"`

說明

• \\(.\\)匹配單個字符
• \\U\\1用大寫版本替換該字符
• no /g表示只處理第一個匹配。

Answer 3

perl好嗎？

$ x=foobar
$ x=$(echo "$x" | perl -pe 's/^(.)/uc($1)/e')
$ echo $x
Foobar