cheat sheets.

Cheat Sheet Title: [ no_spaces_alphanumeric_only ]

Cheat Sheet:
Basic Validations http://ar.rubyonrails.com/classes/ActiveRecord/Validations/ClassMethods.html def validate unless name && name =~ /^\w+$/ errors.add(:name, "is missing or invalid") end end def validate_on_create if User.find_by_name(name) errors.add(:name, "is already being used") end end validates_acceptance_of Validates that the value of the attribute is the string "1" or the value of the :accept parameter. Useful for checkboxes. validates_associated validates_confirmation_of validates_each validates_exclusion_of validates_format_of validates_inclusion_of validates_length_of validates_numericality_of validates_presence_of validates_size_of validates_uniqueness_of DEFAULT_VALIDATION_OPTIONS = { :on => :save, :allow_nil => false, :allow_blank => false, :message => nil ALL_RANGE_OPTIONS = [ :is, :within, :in, :minimum, :maximum ].freeze ALL_NUMERICALITY_CHECK = { :greater_than => '>', :greater_than_or_equal_to => '>=', :equal_to => '==', :less_than => '<', :less_than_or_equal_to => '<=', :odd => 'odd?', :even => 'even?' }.freeze validates_length_of :first_name, :maximum=>30 validates_length_of :last_name, :maximum=>30, :message=>"less than {{count}} if you don't mind" validates_length_of :fax, :in => 7..32, :allow_nil => true validates_length_of :phone, :in => 7..32, :allow_blank => true validates_length_of :user_name, :within => 6..20, :too_long => "pick a shorter name", :too_short => "pick a longer name" validates_length_of :fav_bra_size, :minimum => 1, :too_short => "please enter at least {{count}} character" validates_length_of :smurf_leader, :is => 4, :message => "papa is spelled with {{count}} characters... don't play me." validates_length_of :essay, :minimum => 100, :too_short => "Your essay must be at least {{count}} words."), :tokenizer => lambda {|str| str.scan(/\w+/) }

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