Class: Mechanize::Form

Inherits:
Object
  • Object
show all
Extended by:
ElementMatcher
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/image_button.rb,
lib/mechanize/form/radio_button.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

Methods included from ElementMatcher

elements_with

Constructor Details

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

Returns a new instance of Form.



48
49
50
51
52
53
54
55
56
57
58
59
60
61
 
# File 'lib/mechanize/form.rb', line 48

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

  @encoding = node['accept-charset'] || (page && page.encoding) || nil
  @ignore_encoding_error = false
  parse
end

Dynamic Method Handling

This class handles dynamic methods through the method_missing method

#method_missing(meth, *args) ⇒ Object

Treat form fields like accessors.



154
155
156
157
158
159
160
161
162
163
 
# File 'lib/mechanize/form.rb', line 154

def method_missing(meth, *args)
  method = meth.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.



29
30
31
 
# File 'lib/mechanize/form.rb', line 29

def action
  @action
end

#buttons ⇒ Object (readonly)

Returns the value of attribute buttons.



31
32
33
 
# File 'lib/mechanize/form.rb', line 31

def buttons
  @buttons
end

#checkboxes ⇒ Object (readonly)

Returns the value of attribute checkboxes.



31
32
33
 
# File 'lib/mechanize/form.rb', line 31

def checkboxes
  @checkboxes
end

#encoding ⇒ Object

Character encoding of form data (i.e. UTF-8)



37
38
39
 
# File 'lib/mechanize/form.rb', line 37

def encoding
  @encoding
end

#enctype ⇒ Object

Content-Type for form data (i.e. application/x-www-form-urlencoded)



34
35
36
 
# File 'lib/mechanize/form.rb', line 34

def enctype
  @enctype
end

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

Returns the value of attribute fields.



31
32
33
 
# File 'lib/mechanize/form.rb', line 31

def fields
  @fields
end

#file_uploads ⇒ Object (readonly)

Returns the value of attribute file_uploads.



31
32
33
 
# File 'lib/mechanize/form.rb', line 31

def file_uploads
  @file_uploads
end

#form_node ⇒ Object (readonly)

Returns the value of attribute form_node.



45
46
47
 
# File 'lib/mechanize/form.rb', line 45

def form_node
  @form_node
end

#ignore_encoding_error ⇒ Object

When true, character encoding errors will never be never raised on form submission. Default is false



41
42
43
 
# File 'lib/mechanize/form.rb', line 41

def ignore_encoding_error
  @ignore_encoding_error
end

#method ⇒ Object

Returns the value of attribute method.



29
30
31
 
# File 'lib/mechanize/form.rb', line 29

def method
  @method
end

#name ⇒ Object

Returns the value of attribute name.



29
30
31
 
# File 'lib/mechanize/form.rb', line 29

def name
  @name
end

#page ⇒ Object (readonly)

Returns the value of attribute page.



46
47
48
 
# File 'lib/mechanize/form.rb', line 46

def page
  @page
end

#radiobuttons ⇒ Object (readonly)

Returns the value of attribute radiobuttons.



31
32
33
 
# File 'lib/mechanize/form.rb', line 31

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']



135
136
137
138
 
# File 'lib/mechanize/form.rb', line 135

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'



144
145
146
147
148
149
150
151
 
# File 'lib/mechanize/form.rb', line 144

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



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

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



100
101
102
 
# File 'lib/mechanize/form.rb', line 100

def add_field!(field_name, value = nil)
  fields << Field.new({'name' => 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.



194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
 
# File 'lib/mechanize/form.rb', line 194

def build_query(buttons = [])
  query = []
  @mech.log.info("form encoding: #{encoding}") if @mech && @mech.log

  (fields + checkboxes).sort.each do |f|
    case f
    when Form::CheckBox
      if f.checked
        qval = proc_query(f)
        query.push(*qval)
      end
    when Form::Field
      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 Mechanize::Error,
            "multiple radiobuttons are checked in the same group!"
    end
  end

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

#button ⇒ Object

:method: buttons_with(criteria)

Find all buttons that match criteria Example:

form.buttons_with(:value => /submit/).each do |button|
  button.value = 'hello!'
end



311
 
# File 'lib/mechanize/form.rb', line 311

elements_with :button

#checkbox ⇒ Object

:method: checkboxes_with(criteria)

Find all checkboxes that match criteria Example:

form.checkboxes_with(:name => /woo/).each do |field|
  field.check
end



365
 
# File 'lib/mechanize/form.rb', line 365

elements_with :checkbox,   :checkboxes

#click_button(button = buttons.first) ⇒ Object

Submit form using button. Defaults to the first button.



172
173
174
 
# File 'lib/mechanize/form.rb', line 172

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

#delete_field!(field_name) ⇒ Object

Removes all fields with name field_name.



273
274
275
 
# File 'lib/mechanize/form.rb', line 273

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

#dom_id ⇒ Object

This method is a shortcut to get form’s DOM id. Common usage:

page.form_with(:dom_id => "foorm")

Note that you can also use :id to get to this method:

page.form_with(:id => "foorm")



95
96
97
 
# File 'lib/mechanize/form.rb', line 95

def dom_id
  form_node['id']
end

#field ⇒ Object

:method: fields_with(criteria)

Find all fields that match criteria Example:

form.fields_with(:value => /foo/).each do |field|
  field.value = 'hello!'
end



293
 
# File 'lib/mechanize/form.rb', line 293

elements_with :field

#file_upload ⇒ Object

:method: file_uploads_with(criteria)

Find all file upload fields that match criteria Example:

form.file_uploads_with(:file_name => /picutre/).each do |field|
  field.value = 'foo!'
end



329
 
# File 'lib/mechanize/form.rb', line 329

elements_with :file_upload

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

Returns whether or not the form contains a field with field_name

Returns:

  • (Boolean) 


64
65
66
 
# File 'lib/mechanize/form.rb', line 64

def has_field?(field_name)
  fields.find { |f| f.name == field_name }
end

#has_value?(value) ⇒ Boolean

Returns:

  • (Boolean) 


70
71
72
 
# File 'lib/mechanize/form.rb', line 70

def has_value?(value)
  fields.find { |f| f.value == value }
end

#hidden_field?(field_name) ⇒ Boolean

Returns:

  • (Boolean) 


87
 
# File 'lib/mechanize/form.rb', line 87

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

#hiddens ⇒ Object 



81
 
# File 'lib/mechanize/form.rb', line 81

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

#keys ⇒ Object 



74
 
# File 'lib/mechanize/form.rb', line 74

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

#radiobutton ⇒ Object

:method: radiobuttons_with(criteria)

Find all radio buttons that match criteria Example:

form.radiobuttons_with(:name => /woo/).each do |field|
  field.check
end



347
 
# File 'lib/mechanize/form.rb', line 347

elements_with :radiobutton

#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,



248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
 
# File 'lib/mechanize/form.rb', line 248

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.map do |k,v|
      param_to_multipart(k, v) if k
    end.compact

    params.concat @file_uploads.map { |f| file_to_multipart(f) }

    params.map do |part|
      part.force_encoding('ASCII-8BIT') if part.respond_to? :force_encoding
      "--#{boundary}\r\n#{part}"
    end.join('') +
      "--#{boundary}--\r\n"
  else
    Mechanize::Util.build_query_string(query_params)
  end
end

#reset_button?(button_name) ⇒ Boolean

Returns:

  • (Boolean) 


85
 
# File 'lib/mechanize/form.rb', line 85

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

#resets ⇒ Object 



79
 
# File 'lib/mechanize/form.rb', line 79

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' } )



112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
 
# File 'lib/mechanize/form.rb', line 112

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 if value
        value = val unless value
      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



166
167
168
 
# File 'lib/mechanize/form.rb', line 166

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

#submit_button?(button_name) ⇒ Boolean

Returns:

  • (Boolean) 


84
 
# File 'lib/mechanize/form.rb', line 84

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

#submits ⇒ Object 



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

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

#text_field?(field_name) ⇒ Boolean

Returns:

  • (Boolean) 


86
 
# File 'lib/mechanize/form.rb', line 86

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

#textarea_field?(field_name) ⇒ Boolean

Returns:

  • (Boolean) 


88
 
# File 'lib/mechanize/form.rb', line 88

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

#textareas ⇒ Object 



82
 
# File 'lib/mechanize/form.rb', line 82

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

#texts ⇒ Object 



80
 
# File 'lib/mechanize/form.rb', line 80

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

#values ⇒ Object 



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

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