ruby-condition judgment

=begin       conditional judgment statements include if statements, unless statements, case statements,=end#if  statements =beginif  conditions   then   processing 1elsif  conditions 2 then   processing 2else   processing 3end=enda = 10b =  20if a > b  puts  "A bigger than b" elsif a <  b  puts  "A smaller than b" else  puts  "a is equal  to b "endputs " a bigger than b " if a > b#unless  statement, In contrast to the IF statement, the condition is judged false when the processing =beginunless  condition is executed    processing 1else   processing 2end=enda = 10b =  20unless a > b  puts  "A smaller/same as than b" end# The case  statement, which applies to the comparison object, performs different processing depending on the value of the object, when it can specify multiple values at a time =begincase  compare object when  values 1 then    Handling 1when  Value 2 then   processing 2when  value 3 then   handling 3else   processing 4end= endtags = ["A",   " IMG ", " PRE "]tags.each do |word|  case word  when " P ", " A ",   "I",  "B",  "BLOCKQUOTE"     puts  "#{word} has child."   when  "IMG",  "BR"     puts  "#{word} has child."   else    puts  "#{word} cannoot be used"    Endendarray = ["a", 1, nil]array.each do |word|  case word   when String    puts  "The word is a string"    when numeric     puts  "The word is a numeric"    else    puts  "Other words are something"    endendtext.each_line do |line|  case line  when /^from:/i     puts  "Find a sender"   when /^to:/i    puts  "Find a receiver"   when  /^$/    puts  "Resolution are finnished"     exit   else    break  endend

This article is from the "Invite the Wind" blog, please be sure to keep this source http://yaoyuechengfeng.blog.51cto.com/2958475/1774804

ruby-condition judgment