读取文件并使用bash程序将每一行分成两个变量 [英] Read a file and split each line into two variables with bash program

问题描述

我有一个程序可以在命令行中读取两个单词:

I have a program that reads two words in command line:

#!/bin/bash

if [[ "$1" != "" && "$2" != "" ]]; then
    java -Xmx1024m -cp lib/*:esalib.jar clldsystem.esa.ESAAnalyzer "$1" "$2"
else
    java -Xmx1024m -cp lib/*:esalib.jar clldsystem.esa.ESAAnalyzer
fi

我替换了此代码以逐行从文件读取，这是我必须读取的文件的示例:

I replaced this code to read from a file line by line, this is an example of the file that i must read:

vehicle car
computer program
volley ball

代码读取每一行并将每个单词影响到一个变量，问题出在每一行的拆分过程中，因此它会使$ var1和$ var2成为同一个单词

the code read each line and affect each word to a variable, the problem is in the splitting process of each line so it affec to $var1 and $var2 the same word

#!/bin/bash

while read ligne
do
var1=$(echo $ligne | cut -f1 -d-)
var2=$(echo $ligne | cut -f2 -d-)

if [[ "$var1" != "" && "$var2" != "" ]]; then
    java -Xmx1024m -cp lib/*:esalib.jar clldsystem.esa.ESAAnalyzer "$var1" "$var2"
else
    java -Xmx1024m -cp lib/*:esalib.jar clldsystem.esa.ESAAnalyzer
fi
done < mm.txt

但是新代码没有给出结果

but the new code don't give results

推荐答案

这是调试程序的方式:

#!/bin/bash

while read ligne
do
var1=$(echo $ligne | cut -f1 -d' ')
var2=$(echo $ligne | cut -f2 -d' ')

if [[ "$var1" != "" && "$var2" != "" ]]; then
    echo "$var1" '|' "$var2"
    #java -Xmx1024m -cp lib/*:esalib.jar clldsystem.esa.ESAAnalyzer "$var1" "$var2"
else
    echo "Vars Not Found"
    #java -Xmx1024m -cp lib/*:esalib.jar clldsystem.esa.ESAAnalyzer
fi
done < mm.txt

运行此命令将得到以下输出:

Running this gives the following output:

vehicle car | vehicle car
computer program | computer program
volley ball | volley ball

这意味着您的 cut 命令不正确.您可以通过以下几种方法来解决它:

This means that your cut command is not correct. You have a few options to fix it:

1. 如用户3035772所指出的，使用多变量 read .这不太灵活，因为它依赖于分隔符为 $ IFS ，您暗中不同意.
2. 将 mm.txt 中的定界符固定为-，作为 cut 的 -d-标志命令要求:汽车计算机程序排球
3. 修复 cut 命令以要求使用空格分隔符，就像在 mm.txt 中一样: cut -f1 -d''.

1. Use multi-variable read as user3035772 pointed out. This is less flexible because it relies on the separator being $IFS, which you are implicitly not agreeing to.
2. Fix the delimiter in mm.txt to be - as the -d- flag of the cut command requires: vehicle-car computer-program volley-ball
3. Fix the cut command to require a space delimiter as you have in mm.txt: cut -f1 -d' '.

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