linux shell之字符串的更具字符分割和删除字符和文本内容的删除以及内容是否匹配成功

1  字符串的更具字符分割

1） xargs分割

  

   

    

     

    
    

     

      echo "chenyu*hello*word" | xargs -d "*"
     
    
   

    

     

    
    

     

      chenyu hello word
     
    
  
 

2） awk分割

  

   

    

     

    
    

     

      echo "chenyu*hello*word" | awk -F "*" '{print $1}'
     
    
   

    

     

    
    

     

      chenyu
     
    
  
 

2 字符串的删除字符

1）用tr命令

  

   

    

     

    
    

     

      echo "chenyu ni hao ya" | tr -d 'y' 
     
    
   

    

     

    
    

     

      chenu ni hao a
     
    
  
 

2）用sed命令

  

   

    

     

    
    

     

      echo  "hello*word*word" | sed 's/*//g'
     
    
   

    

     

    
    

     

      hellowordword
     
    
  
 

3 文本内容的删除

用sed命令

  

   

    

     

    
    

     

      cat 1.txt
     
    
   

    

     

    
    

     

      chenyu
     
    
   

    

     

    
    

     

      nihao
     
    
   

    

     

    
    

     

      hello
     
    
   

    

     

    
    

     

      word
     
    
   

    

     

    
    

     

      chenyu
     
    
   

    

     

    
    

     

      nihao
     
    
   

    

     

    
    

     

      dongma
     
    
   

    

     

    
    

     

      sed -i '/chenyu/d' 1.txt
     
    
   

    

     

    
    

     

      cat 1.txt
     
    
   

    

     

    
    

     

      nihao
     
    
   

    

     

    
    

     

      hello
     
    
   

    

     

    
    

     

      word
     
    
   

    

     

    
    

     

      nihao
     
    
   

    

     

    
    

     

      dongma
     
    
  
 

4 grep -q 用于if逻辑判断

-q 参数，本意是 Quiet; do not write anything to standard output. Exit immediately with zero status if any match is found, even if an error was detected.  中文意思为，安静模式，不打印任何标准输出。如果有匹配的内容则立即返回状态值0

自己测试如下

  

   

    

     

    
    

     

      #/bin/bash
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     

      value="chenyu ni hao ya"
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     

      #匹配成功执行$?返回0
     
    
   

    

     

    
    

     

      echo "hello" | grep -q "he";
     
    
   

    

     

    
    

     

      echo $?
     
    
   

    

     

    
    

     

      #匹配失败执行$?非0
     
    
   

    

     

    
    

     

      echo "hello" | grep -q "hehelodaf";
     
    
   

    

     

    
    

     

      echo $?
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     

      #如果能匹配成功那么就到then反之到else
     
    
   

    

     

    
    

     

      if echo $value | grep -q "chenyuddsa"; 
     
    
   

    

     

    
    

     

      then
     
    
   

    

     

    
    

     
   echo "first success" 
     
    
   

    

     

    
    

     

      else
     
    
   

    

     

    
    

     
   echo "first fail"
     
    
   

    

     

    
    

     

      fi
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     

      if echo $value | grep -q "hao"; 
     
    
   

    

     

    
    

     

      then
     
    
   

    

     

    
    

     
   echo "second success" 
     
    
   

    

     

    
    

     

      else
     
    
   

    

     

    
    

     
   echo "second fail"
     
    
   

    

     

    
    

     

      fi
     
    
  
 

允许结果如下：

  

   

    

     

    
    

     

      ./grep.sh
     
    
   

    

     

    
    

     

      0
     
    
   

    

     

    
    

     

      1
     
    
   

    

     

    
    

     

      first fail
     
    
   

    

     

    
    

     

      second success
     
    
  
 

5 grep -i（忽略大小写）来判断结果

  

   

    

     

    
    

     

      #/bin/bash
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     

      value="chenyu"
     
    
   

    

     

    
    

     

      echo $value | grep -i "chen" > /dev/null
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     

      if [ $? -eq 0 ];
     
    
   

    

     

    
    

     

      then
     
    
   

    

     

    
    

     
	echo "grep success"
     
    
   

    

     

    
    

     

      else
     
    
   

    

     

    
    

     
	echo "grep fail"
     
    
   

    

     

    
    

     

      fi
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     

      echo $value | grep -i "chengongyu" > /dev/null
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     

      if [ $? -eq 0 ];
     
    
   

    

     

    
    

     

      then
     
    
   

    

     

    
    

     
	echo "grep success"
     
    
   

    

     

    
    

     

      else
     
    
   

    

     

    
    

     
	echo "grep fail"
     
    
   

    

     

    
    

     

      fi
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     
 
     
    
  
 

运行结果

  

   

    

     

    
    

     

      grep success
     
    
   

    

     

    
    

     

      grep fail
     
    
  
 

文章来源: chenyu.blog.csdn.net，作者：chen.yu，版权归原作者所有，如需转载，请联系作者。

原文链接：chenyu.blog.csdn.net/article/details/88636503