Can't get ASCII art to echo to console

问题

I'm new to Bash scripting, and this here is just puzzling to me. I'm adding ASCII art to a project, and can't seem to figure out how to escape certain characters. Would someone please help me get the following code below to work?

Whenever I tried adding slashes as escape characters to fix the errors, the slashes also wound up printing to console on execution. This ruins the image. I don't understand what I'm doing wrong, so I've posted the code below in the hopes that someone will take a moment to show me the right way. Please? I've removed the quotes to prevent more clutter.

echo -en "\E[31m"
echo
echo       _,.
echo     ,` -.)
echo    '( _/'-\\-.              
echo   /,|`--._,-^|          ,    
echo   \_| |`-._/||          ,'|      
echo     |  `-, / |         /  /     
echo     |     || |        /  /      
echo      `r-._||/   __   /  / 
echo  __,-<_     )`-/  `./  /
echo '  \   `---'   \   /  /
echo     |           |./  / 
echo     /           //  /    
echo \_/' \         |/  /        
echo  |    |   _,^-'/  /             
echo  |    , ``  (\/  /_       
echo   \,.->._    \X-=/^        
echo   (  /   `-._//^` 
echo    `Y-.____(__}             
echo     |     {__)          
echo           ()`

回答1:

Quotes in bash are important syntactic elements, not clutter. However, to print ASCII art, save yourself the trouble of proper quoting and escaping and just use a here document:

cat << "EOF"
       _,.
     ,` -.)
    '( _/'-\\-.               
   /,|`--._,-^|            ,     
   \_| |`-._/||          ,'|       
     |  `-, / |         /  /      
     |     || |        /  /       
      `r-._||/   __   /  /  
  __,-<_     )`-/  `./  /
 '  \   `---'   \   /  / 
     |           |./  /  
     /           //  /     
 \_/' \         |/  /         
  |    |   _,^-'/  /              
  |    , ``  (\/  /_        
   \,.->._    \X-=/^         
   (  /   `-._//^`  
    `Y-.____(__}              
     |     {__)           
           ()`     
EOF

Make sure not to remove the quotes here. They are not optional.

回答2:

echo takes a series of arguments. If you type

echo  foo      bar

the echo command gets two arguments, "foo" and "bar", and the spacing between the words is discarded.

For what you're trying to do, you probably want echo to receive exactly one argument for each line. In bash, the easiest way is probably to use so-called "ANSI-C Quoting". Within each string, each apostrophe ' and backslash \ character has to be escaped with a backslash.

Here's a version of your script using this method:

#!/bin/bash

echo -n $'\E[31m'
echo $''
echo $'      _,.'
echo $'    ,` -.)'
echo $'   \'( _/\'-\\\\-.'
echo $'  /,|`--._,-^|          ,'
echo $'  \\_| |`-._/||          ,\'|'
echo $'    |  `-, / |         /  /'
echo $'    |     || |        /  /'
echo $'     `r-._||/   __   /  /'
echo $' __,-<_     )`-/  `./  /'
echo $'\'  \\   `---\'   \\   /  /'
echo $'    |           |./  /'
echo $'    /           //  /'
echo $'\\_/\' \\         |/  /'
echo $' |    |   _,^-\'/  /'
echo $' |    , ``  (\\/  /_'
echo $'  \\,.->._    \\X-=/^'
echo $'  (  /   `-._//^`'
echo $'   `Y-.____(__}'
echo $'    |     {__)'
echo $'          ()`'

(The added backslashes do mess up the picture in the script, but it appears correctly on output.)

For this case, that other guy's answer is a better approach, since it avoids the need to escape any of the special characters, but this technique could be useful for smaller output.

Or you could just put the raw picture into a file and cat it to standard output.

来源：https://stackoverflow.com/questions/25214084/cant-get-ascii-art-to-echo-to-console

标签

bash

scripting

syntax-error

ascii