编号数组元素

编号数组元素 - Bash脚本(Numbering Array Elements - Bash Scripting)

我有一个名为c的数组。 它的元素是在当前目录中找到的文件名。 我如何在他们自己的行上列出他们之前的数字？ 例如：

1. aaa 2. filename2 3. bbb 4. asdf

我现在的代码只是在自己的行上打印每个文件。 喜欢：

aaa filename2 bbb asdf

我的代码如下：

#!/bin/bash c=( $(ls --group-directories-first $*) ) printf '%s\n' "${c[@]}"

I have an array named c. Its elements are filenames found in the current directory. How do I list them on their own line with a number before? For example:

1. aaa 2. filename2 3. bbb 4. asdf

The code I have now just prints each file on its own line. Like:

aaa filename2 bbb asdf

My code is below:

#!/bin/bash c=( $(ls --group-directories-first $*) ) printf '%s\n' "${c[@]}"

最满意答案

从数组c开始，这里有三种方法：

用cat -n

cat实用程序将编号输出行：

$ cat -n < <(printf "%s\n" "${c[@]}") 1 aaa 2 filename2 3 bbb 4 asdf

使用bash

此方法使用shell算法对行进行编号：

$ count=0; for f in "${c[@]}"; do echo "$((++count)). $f"; done 1. aaa 2. filename2 3. bbb 4. asdf

使用nl

在评论中，twalberg建议使用nl ：

$ nl < <(printf "%s\n" "${c[@]}") 1 aaa 2 filename2 3 bbb 4 asdf

实用程序nl具有许多选项，用于精确控制编辑的编排方式，包括例如左/右对齐，包含前导零。 见man nl 。

Starting with array c, here are three methods:

Using cat -n

The cat utility will number output lines:

$ cat -n < <(printf "%s\n" "${c[@]}") 1 aaa 2 filename2 3 bbb 4 asdf

Using bash

This method uses shell arithmetic to number the lines:

$ count=0; for f in "${c[@]}"; do echo "$((++count)). $f"; done 1. aaa 2. filename2 3. bbb 4. asdf

Using nl

In the comments, twalberg suggests the use of nl:

$ nl < <(printf "%s\n" "${c[@]}") 1 aaa 2 filename2 3 bbb 4 asdf

The utility nl has a number of options for controlling exactly how you want the numbering done including, for example, left/right justification, inclusion of leading zeros. See man nl.