Ruby Case語句


在Ruby中,使用’case‘代替’switch‘關鍵字,以及使用’when‘代替’case‘關鍵字。 case語句將一個語句與多個條件進行匹配,就像其他語言中的switch語句一樣。

語法:

case expression  
[when expression [, expression ...] [then]  
   code ]...  
[else  
   code ]  
end

程式碼範例:

#!/usr/bin/ruby   
print "Enter your day: "   
day = gets.chomp   
case day   
    when "2"   
      puts '穿紅色和白色?'   
    when "3"   
      puts 'Wear Green'   
    when "4"   
      puts 'Wear Yellow'   
     when "5"   
      puts 'Wear White'   
     when "6"   
      puts 'Wear Black'   
    else   
      puts "Wear Any color"   
end

將上面程式碼儲存到檔案:case-statement.rb中,執行上面程式碼,得到以下結果 -

F:\worksp\ruby>ruby case-statement.rb
Enter your day: 3
Wear Any color

F:\worksp\ruby>ruby case-statement.rb
Enter your day: 2
穿紅色和白色?

F:\worksp\ruby>ruby case-statement.rb
Enter your day: 3
Wear Green

F:\worksp\ruby>ruby case-statement.rb
Enter your day: 5
Wear White

F:\worksp\ruby>