如何使用SED / AWK替换一个逗号分隔的字符串的第n列/字段？ [英] How to replace the nth column/field in a comma-separated string using sed/awk?

问题描述

假设我有一个字符串

"1,2,3,4"

现在我要替换，如通过一些不同的值串的第3字段

Now I want to replace, e.g. the 3rd field of the string by some different value.

"1,2,NEW,4"

我设法用下面的命令来做到这一点：

I managed to do this with the following command:

echo "1,2,3,4" | awk -F, -v OFS=, '{$3="NEW"; print }'

现在的指数为要被替换的列应作为变量进行传递。因此，在这种情况下

Now the index for the column to be replaced should be passed as a variable. So in this case

index=3

我怎样才能把它传递给AWK？因为这是不行的：

How can I pass this to awk? Because this won't work:

echo "1,2,3,4" | awk -F, -v OFS=, '{$index="NEW"; print }'
echo "1,2,3,4" | awk -F, -v OFS=, '{$($index)="NEW"; print }'
echo "1,2,3,4" | awk -F, -v OFS=, '{\$$index="NEW"; print }'

感谢您的帮助！

推荐答案

有壳插在awk程序索引：

Have the shell interpolate the index in the awk program:

echo "1,2,3,4" | awk -F, -v OFS=, '{$'$index'="NEW"; print }'

请注意最初单引号awk程序是如何在三个部分分割，单个引开始'{$'，内插指数值，接着程序的单引号其余

Note how the originally single quoted awk program is split in three parts, a single quoted beginning '{$', the interpolated index value, followed by the single quoted remainder of the program.

这篇关于如何使用SED / AWK替换一个逗号分隔的字符串的第n列/字段？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！