Introduction to Shell arrays

Introduction to Shell arrays

Time: 2008-01-23 10:57:33 Source: Linux Federation Collection collation Author:

You can also use array variables in bash, which are assigned two types of values: (1) name = (value1 ... valuen) at this time subscript starting from 0 (2) Name[index] = value There is no limit to the scope of the array subscript, and there is no need to use successive components. -------------------------------------------------------------------------------- $ a= (A b c def) ================================================== $ echo ${a[@]}//Take all elements A b c def ================================================= $ echo ${a[0]}//Take first element A ================================================= To get the number of array elements $ echo ${#A [@]} 4 $ echo ${#A} 4 $ echo ${#A [3]}//Get the length of element 3 $ ================================================== $ a[3]=yaoshuyin//re-assign the third element $ echo ${a[@]} A b c yaoshuyin ================================================== Clear variables $ unset A $ echo ${a[@]} $ ================================================== Empty the variable, and the value becomes empty $ a= $ echo ${a[@]} $ ================================================== A=b B=c Unset $A The fact that the variable being canceled is B instead of a ======================= example While loop ======================== #建立数组 Arrsource= ("arrjobs.php" "arrsubhangye.php" "arrfirst.php") arrdest= ("BUILDHR" \ "Buildtrain/htdocs" \ "Bankhr" \ "Healthr" \ "Elehr" \ ) #取数组无元素个数 lenarrsource=${#arrSource} lenarrdest=${#arrDest} #循环列出数组元素 I=0 While [$i-lt $lenArrSource] Todo echo ${arrsource[$i]} Let i++ Done I=0 While [$i-lt $lenArrDest] Todo echo ${arrdest[$i]} Let i++ Done ======================= Example: For loop =============================== #源文件 Arrsource= ("/home/800hr/htdocs/login_jump.php") #目标网站 arrDest=(ithr elehr buildhr bankhr healthr ctvhr chenhr mechr clothr cneduhr 56hr tourhr foodhr greenhr cnlawhr waimaohr) For outer in ${arrsource} #${arrsource} is an array of all elements Todo For inner in ${arrdest} Todo echo "Ln-s $outer/home/${inner}/campus/" Done Done