如何将对象的字段转储到控制台？

当我运行一个简单的Ruby脚本时，将对象的字段转储到控制台的最简单方法是什么？

我正在寻找类似于PHP的东西print_r()，也可以与数组一起使用。

可能：

puts variable.inspect

您可能会发现methods方法的用途，该方法返回对象的方法数组。它与并不相同print_r，但有时仍然有用。

>> "Hello".methods.sort
=> ["%", "*", "+", "<", "<<", "<=", "<=>", "==", "===", "=~", ">", ">=", "[]", "[]=", "__id__", "__send__", "all?", "any?", "between?", "capitalize", "capitalize!", "casecmp", "center", "chomp", "chomp!", "chop", "chop!", "class", "clone", "collect", "concat", "count", "crypt", "delete", "delete!", "detect", "display", "downcase", "downcase!", "dump", "dup", "each", "each_byte", "each_line", "each_with_index", "empty?", "entries", "eql?", "equal?", "extend", "find", "find_all", "freeze", "frozen?", "grep", "gsub", "gsub!", "hash", "hex", "id", "include?", "index", "inject", "insert", "inspect", "instance_eval", "instance_of?", "instance_variable_defined?", "instance_variable_get", "instance_variable_set", "instance_variables", "intern", "is_a?", "is_binary_data?", "is_complex_yaml?", "kind_of?", "length", "ljust", "lstrip", "lstrip!", "map", "match", "max", "member?", "method", "methods", "min", "next", "next!", "nil?", "object_id", "oct", "partition", "private_methods", "protected_methods", "public_methods", "reject", "replace", "respond_to?", "reverse", "reverse!", "rindex", "rjust", "rstrip", "rstrip!", "scan", "select", "send", "singleton_methods", "size", "slice", "slice!", "sort", "sort_by", "split", "squeeze", "squeeze!", "strip", "strip!", "sub", "sub!", "succ", "succ!", "sum", "swapcase", "swapcase!", "taguri", "taguri=", "taint", "tainted?", "to_a", "to_f", "to_i", "to_s", "to_str", "to_sym", "to_yaml", "to_yaml_properties", "to_yaml_style", "tr", "tr!", "tr_s", "tr_s!", "type", "unpack", "untaint", "upcase", "upcase!", "upto", "zip"]

该to_yaml方法有时似乎很有用：

$foo = {:name => "Clem", :age => 43}

puts $foo.to_yaml

退货

--- 
:age: 43
:name: Clem

（这是否取决于YAML正在加载的某些模块？还是通常可用？）

p object

的Ruby文档p。

p(*args) public

对于每个对象，直接在程序的标准输出中写入obj.inspect，后跟换行符。

如果仅在对象中查找实例变量，则这可能会很有用：

obj.instance_variables.map do |var|
  puts [var, obj.instance_variable_get(var)].join(":")
end

或作为单行复制和粘贴：

obj.instance_variables.map{|var| puts [var, obj.instance_variable_get(var)].join(":")}

把foo.to_json

可能会派上用场，因为默认情况下会加载json模块

如果要打印已经缩进的JSON：

require 'json'
...
puts JSON.pretty_generate(JSON.parse(object.to_json))

我遇到了这个线程，因为我正在寻找类似的东西。我喜欢这些答复，他们给了我一些想法，因此我测试了.to_hash方法，并且在用例上也非常有效。：

object.to_hash

object.attribute_names

# => ["id", "name", "email", "created_at", "updated_at", "password_digest", "remember_token", "admin", "marketing_permissions", "terms_and_conditions", "disable", "black_list", "zero_cost", "password_reset_token", "password_reset_sent_at"]


object.attributes.values

# => [1, "tom", "tom@tom.com", Tue, 02 Jun 2015 00:16:03 UTC +00:00, Tue, 02 Jun 2015 00:22:35 UTC +00:00, "$2a$10$gUTr3lpHzXvCDhVvizo8Gu/MxiTrazOWmOQqJXMW8gFLvwDftF9Lm", "2dd1829c9fb3af2a36a970acda0efe5c1d471199", true, nil, nil, nil, nil, nil, nil, nil]