Class: Mechanize::Form

Inherits:
Object
  • Object
show all
Defined in:
lib/mechanize/form.rb,
lib/mechanize/inspect.rb,
lib/mechanize/form/field.rb,
lib/mechanize/form/button.rb,
lib/mechanize/form/option.rb,
lib/mechanize/monkey_patch.rb,
lib/mechanize/form/check_box.rb,
lib/mechanize/form/file_upload.rb,
lib/mechanize/form/select_list.rb,
lib/mechanize/form/image_button.rb,
lib/mechanize/form/radio_button.rb,
lib/mechanize/form/multi_select_list.rb

Overview

Synopsis

This class encapsulates a form parsed out of an HTML page. Each type of input fields available in a form can be accessed through this object. See GlobalForm for more methods.

Example

Find a form and print out its fields

form = page.forms.first # => Mechanize::Form
form.fields.each { |f| puts f.name }

Set the input field ‘name’ to “Aaron”

form['name'] = 'Aaron'
puts form['name']

Defined Under Namespace

Classes: Button, CheckBox, Field, FileUpload, Hidden, ImageButton, MultiSelectList, Option, RadioButton, Reset, SelectList, Submit, Text, Textarea

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(node, mech = nil, page = nil) ⇒ Form

Returns a new instance of Form.



35
36
37
38
39
40
41
42
43
44
45
46
 
# File 'lib/mechanize/form.rb', line 35

def initialize(node, mech=nil, page=nil)
  @enctype = node['enctype'] || 'application/x-www-form-urlencoded'
  @form_node        = node
  @action           = Util.html_unescape(node['action'])
  @method           = (node['method'] || 'GET').upcase
  @name             = node['name']
  @clicked_buttons  = []
  @page             = page
  @mech             = mech

  parse
end

Dynamic Method Handling

This class handles dynamic methods through the method_missing method

#method_missing(id, *args) ⇒ Object

Treat form fields like accessors.



130
131
132
133
134
135
136
137
 
# File 'lib/mechanize/form.rb', line 130

def method_missing(id,*args)
  method = id.to_s.gsub(/=$/, '')
  if field(method)
    return field(method).value if args.empty?
    return field(method).value = args[0]
  end
  super
end

Instance Attribute Details

#action ⇒ Object

Returns the value of attribute action.



25
26
27
 
# File 'lib/mechanize/form.rb', line 25

def action
  @action
end

#buttons ⇒ Object (readonly)

Returns the value of attribute buttons.



27
28
29
 
# File 'lib/mechanize/form.rb', line 27

def buttons
  @buttons
end

#checkboxes ⇒ Object (readonly)

Returns the value of attribute checkboxes.



27
28
29
 
# File 'lib/mechanize/form.rb', line 27

def checkboxes
  @checkboxes
end

#enctype ⇒ Object

Returns the value of attribute enctype.



28
29
30
 
# File 'lib/mechanize/form.rb', line 28

def enctype
  @enctype
end

#fields ⇒ Object (readonly) Also known as: elements

Returns the value of attribute fields.



27
28
29
 
# File 'lib/mechanize/form.rb', line 27

def fields
  @fields
end

#file_uploads ⇒ Object (readonly)

Returns the value of attribute file_uploads.



27
28
29
 
# File 'lib/mechanize/form.rb', line 27

def file_uploads
  @file_uploads
end

#form_node ⇒ Object (readonly)

Returns the value of attribute form_node.



32
33
34
 
# File 'lib/mechanize/form.rb', line 32

def form_node
  @form_node
end

#method ⇒ Object

Returns the value of attribute method.



25
26
27
 
# File 'lib/mechanize/form.rb', line 25

def method
  @method
end

#name ⇒ Object

Returns the value of attribute name.



25
26
27
 
# File 'lib/mechanize/form.rb', line 25

def name
  @name
end

#page ⇒ Object (readonly)

Returns the value of attribute page.



33
34
35
 
# File 'lib/mechanize/form.rb', line 33

def page
  @page
end

#radiobuttons ⇒ Object (readonly)

Returns the value of attribute radiobuttons.



27
28
29
 
# File 'lib/mechanize/form.rb', line 27

def radiobuttons
  @radiobuttons
end

Instance Method Details

#[](field_name) ⇒ Object

Fetch the value of the first input field with the name passed in

Example

Fetch the value set in the input field ‘name’

puts form['name']



111
112
113
114
 
# File 'lib/mechanize/form.rb', line 111

def [](field_name)
  f = field(field_name)
  f && f.value
end

#[]=(field_name, value) ⇒ Object

Set the value of the first input field with the name passed in

Example

Set the value in the input field ‘name’ to “Aaron”

form['name'] = 'Aaron'



120
121
122
123
124
125
126
127
 
# File 'lib/mechanize/form.rb', line 120

def []=(field_name, value)
  f = field(field_name)
  if f.nil?
    add_field!(field_name, value)
  else
    f.value = value
  end
end

#add_button_to_query(button) ⇒ Object

This method adds a button to the query. If the form needs to be submitted with multiple buttons, pass each button to this method.



217
218
219
 
# File 'lib/mechanize/form.rb', line 217

def add_button_to_query(button)
  @clicked_buttons << button
end

#add_field!(field_name, value = nil) ⇒ Object

Add a field with field_name and value



76
77
78
 
# File 'lib/mechanize/form.rb', line 76

def add_field!(field_name, value = nil)
  fields << Field.new(field_name, value)
end

#build_query(buttons = []) ⇒ Object

This method builds an array of arrays that represent the query parameters to be used with this form. The return value can then be used to create a query string for this form.



173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
 
# File 'lib/mechanize/form.rb', line 173

def build_query(buttons = [])
  query = []

  fields().each do |f|
    qval = proc_query(f)
    query.push(*qval)
  end

  checkboxes().each do |f|
    if f.checked
      qval = proc_query(f)
      query.push(*qval)
    end
  end

  radio_groups = {}
  radiobuttons().each do |f|
    fname = from_native_charset(f.name)
    radio_groups[fname] ||= []
    radio_groups[fname] << f
  end

  # take one radio button from each group
  radio_groups.each_value do |g|
    checked = g.select {|f| f.checked}

    if checked.size == 1
      f = checked.first
      qval = proc_query(f)
      query.push(*qval)
    elsif checked.size > 1
      raise "multiple radiobuttons are checked in the same group!"
    end
  end

  @clicked_buttons.each { |b|
    qval = proc_query(b)
    query.push(*qval)
  }
  query
end

#click_button(button = buttons.first) ⇒ Object

Submit form using button. Defaults to the first button.



146
147
148
 
# File 'lib/mechanize/form.rb', line 146

def click_button(button = buttons.first)
  submit(button)
end

#delete_field!(field_name) ⇒ Object

Removes all fields with name field_name.



241
242
243
 
# File 'lib/mechanize/form.rb', line 241

def delete_field!(field_name)
  @fields.delete_if{ |f| f.name == field_name}
end

#has_field?(field_name) ⇒ Boolean Also known as: has_key?

Returns whether or not the form contains a field with field_name

Returns:

  • (Boolean) 


49
50
51
 
# File 'lib/mechanize/form.rb', line 49

def has_field?(field_name)
  ! fields.find { |f| f.name.eql? field_name }.nil?
end

#has_value?(value) ⇒ Boolean

Returns:

  • (Boolean) 


55
56
57
 
# File 'lib/mechanize/form.rb', line 55

def has_value?(value)
  ! fields.find { |f| f.value.eql? value }.nil?
end

#hidden_field?(field_name) ⇒ Boolean

Returns:

  • (Boolean) 


72
 
# File 'lib/mechanize/form.rb', line 72

def hidden_field?(field_name)   !!  hiddens.find{|f| f.name == field_name}; end

#hiddens ⇒ Object 



66
 
# File 'lib/mechanize/form.rb', line 66

def hiddens  ; @hiddens   ||=  fields.select { |f| f.class == Hidden   }; end

#keys ⇒ Object 



59
 
# File 'lib/mechanize/form.rb', line 59

def keys; fields.map { |f| f.name }; end

#pretty_print(q) ⇒ Object 



55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
 
# File 'lib/mechanize/inspect.rb', line 55

def pretty_print(q)
  q.object_group(self) {
    q.breakable; q.group(1, '{name', '}') { q.breakable; q.pp name }
    q.breakable; q.group(1, '{method', '}') { q.breakable; q.pp method }
    q.breakable; q.group(1, '{action', '}') { q.breakable; q.pp action }
    q.breakable; q.group(1, '{fields', '}') {
      fields.each do |field|
        q.breakable
        q.pp field
      end
    }
    q.breakable; q.group(1, '{radiobuttons', '}') {
      radiobuttons.each { |b| q.breakable; q.pp b }
    }
    q.breakable; q.group(1, '{checkboxes', '}') {
      checkboxes.each { |b| q.breakable; q.pp b }
    }
    q.breakable; q.group(1, '{file_uploads', '}') {
      file_uploads.each { |b| q.breakable; q.pp b }
    }
    q.breakable; q.group(1, '{buttons', '}') {
      buttons.each { |b| q.breakable; q.pp b }
    }
  }
end

#request_data ⇒ Object

This method calculates the request data to be sent back to the server for this form, depending on if this is a regular post, get, or a multi-part post,



224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
 
# File 'lib/mechanize/form.rb', line 224

def request_data
  query_params = build_query()
  case @enctype.downcase
  when /^multipart\/form-data/
    boundary = rand_string(20)
    @enctype = "multipart/form-data; boundary=#{boundary}"
    params = []
    query_params.each { |k,v| params << param_to_multipart(k, v) unless k.nil? }
    @file_uploads.each { |f| params << file_to_multipart(f) }
    params.collect { |p| "--#{boundary}\r\n#{p}" }.join('') +
      "--#{boundary}--\r\n"
  else
    Mechanize::Util.build_query_string(query_params)
  end
end

#reset_button?(button_name) ⇒ Boolean

Returns:

  • (Boolean) 


70
 
# File 'lib/mechanize/form.rb', line 70

def reset_button?(button_name)  !!   resets.find{|f| f.name == button_name}; end

#resets ⇒ Object 



64
 
# File 'lib/mechanize/form.rb', line 64

def resets   ; @resets    ||= buttons.select { |f| f.class == Reset    }; end

#set_fields(fields = {}) ⇒ Object

This method sets multiple fields on the form. It takes a list of field name, value pairs. If there is more than one field found with the same name, this method will set the first one found. If you want to set the value of a duplicate field, use a value which is a Hash with the key as the index in to the form. The index is zero based. For example, to set the second field named ‘foo’, you could do the following:

form.set_fields( :foo => { 1 => 'bar' } )



88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
 
# File 'lib/mechanize/form.rb', line 88

def set_fields(fields = {})
  fields.each do |k,v|
    case v
    when Hash
      v.each do |index, value|
        self.fields_with(:name => k.to_s).[](index).value = value
      end
    else
      value = nil
      index = 0
      [v].flatten.each do |val|
        index = val.to_i unless value.nil?
        value = val if value.nil?
      end
      self.fields_with(:name => k.to_s).[](index).value = value
    end
  end
end

#submit(button = nil, headers = {}) ⇒ Object

Submit this form with the button passed in



140
141
142
 
# File 'lib/mechanize/form.rb', line 140

def submit button=nil, headers = {}
  @mech.submit(self, button, headers)
end

#submit_button?(button_name) ⇒ Boolean

Returns:

  • (Boolean) 


69
 
# File 'lib/mechanize/form.rb', line 69

def submit_button?(button_name) !!  submits.find{|f| f.name == button_name}; end

#submits ⇒ Object 



63
 
# File 'lib/mechanize/form.rb', line 63

def submits  ; @submits   ||= buttons.select { |f| f.class == Submit   }; end

#text_field?(field_name) ⇒ Boolean

Returns:

  • (Boolean) 


71
 
# File 'lib/mechanize/form.rb', line 71

def text_field?(field_name)     !!    texts.find{|f| f.name == field_name}; end

#textarea_field?(field_name) ⇒ Boolean

Returns:

  • (Boolean) 


73
 
# File 'lib/mechanize/form.rb', line 73

def textarea_field?(field_name) !!textareas.find{|f| f.name == field_name}; end

#textareas ⇒ Object 



67
 
# File 'lib/mechanize/form.rb', line 67

def textareas; @textareas ||=  fields.select { |f| f.class == Textarea }; end

#texts ⇒ Object 



65
 
# File 'lib/mechanize/form.rb', line 65

def texts    ; @texts     ||=  fields.select { |f| f.class == Text     }; end

#values ⇒ Object 



61
 
# File 'lib/mechanize/form.rb', line 61

def values; fields.map { |f| f.value }; end