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6 . Create another new view template for theapplication, app\views\ look\at . rhtml:

Using HTML Control ShortcutsThis application uses Rails HTML control shortcuts .

Your name is .

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7 . Start the WEBrick server:

C:\rubydev\textfield2>ruby script/serverYou pass the start_form_tag method aspecifying the action, and an optional hashspecifying options the two possible options

are :method , which can be get or post and:multipart , which can be true or false .

There s also a check_box_tag method to

create checkboxes, a radio_button_tagmethod to create radio buttons, and so on .

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How to use Check box in rails? at }, {:method

=> post }) %>Would you like a raise?

Yes

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A nd you set up the controller named look withtwo actions, input and at :

class LookController < A pplicationControllerdef at

@data = params[:check1]enddef input

endend

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Finally views\look\at .rhtml, looks like ..

Reading data from checkboxesThis Ruby on Rails application reads data from

checkboxes .

You clicked yes .

You did not click yes .

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Using select ControlWorking With Select ControlsThis Ruby on Rails application lets you read data

from select controls .
at }, {:method

=> post }) %>Select your new car s color .

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true}) %>

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Working with Models

To use a model, follow these steps:1 . Create a new application named modeler:C:\rubydev>Rails modeler

2 . Change directories to the modeler directory:C:\rubydev>cd modelerC:\rubydevmodeler>

3 . A dd a controller named look:C:\rubydev\modeler> ruby script/generatecontroller Look

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4 . Create a new file, app\models\cruncher . rb,placing this code in that file:

class Cruncherdef crunchreturn 5

endend

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5. Edit app\controllers\look_controller . rb,adding this code:

class LookController < A pplicationControllerdef at@cruncher = Cruncher .new@data = @cruncher .crunchend

end

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6 . Create a new view template for theapplication, app\views\look\at .rhtml:

Working With Models
This application fetches data from a model .
The fetched data is: .

7 . Start the WEBrick server:

C:\rubydev\modeler>ruby script/server

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creating an object of the Cruncher class andcalling the crunch method to recover the datafrom the model:

class LookController < A pplicationControllerdef at@cruncher = Cruncher .new@data = @cruncher .crunchendend

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Tie a Text Field to a Model

1.

Create a new application named textfields3:C:\rubydev\ch0 5 >Rails textfields3

2 . Change directories to the textfields3

directory:C:\rubydev> cd textfields3C:\rubydev\textfields3>

3 . A dd a controller named look:C:\rubydev\textfields3> ruby script/generate

controller Look

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4 . Edit \app\controllers\look_cotroller . rb, addingthis code:

class LookController < A pplicationControllerdef at@data_hash = params[:cruncher]

@cruncher = Cruncher .new(@data_hash[:crunch])@data = @cruncher .crunchend

def inputendend

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5. Create a new file, \app\models\cruncher . rb,add this code

class Cruncherattr_reader :crunchattr_writer :crunchdef initialize(data)@crunch = dataendend

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6 . Create a new view template for theapplication,\app\views\look\ input . rhtml:

Working With Text FieldsThis Ruby on Rails application lets you read data from text

fields .

at }, {:method =>post }) %>Please enter your name .

30}) %>

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7 . Create another new view template for theapplication, \app\views\look\at . rhtml :

Using HTML Control ShortcutsThis application uses Rails HTML control shortcuts .

Your name is .

8 . Start the WEBrick server:

C:\rubydev\textfield3> ruby script/server

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Storing Data in Sessions

A session is made up of memory on the server,and you access that memory using the hashnamed session.To store a data item in the session, you justplace it in the session hash using a key:session [:data] = @dataThen, when you want to recover that datawhen the same or another action is called

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The data in a session isn t permanent. Bydefault it times out after 15-20 minutes of

inactivity on the user s part.To store data in a session, follow these steps

1 . Create a new application named sessions :C:\rubydev> Rails sessions

2 . Change directories to the sessions directory:C:\rubydev> cd sessionsC:\rubydev\sessions>

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3 . A dd a controller named look :C:\rubydev\sessions> ruby script/generate

controller Look4 . open look_controller . rb, and add following this

code

class LookController post }) %>

Counter 1: .

Counter 2: .

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6 . Start the WEBrick server:

C:\rubydev\sessions>ruby script/server7 . Navigate tohttp://localhost:3000/look/input . Theapplication displays the values of two

counters in the web page . Counter 1 is notstored in a session, But Counter 2 is stored inthe session, Counter 1 is reinitialized each

time you call the action

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How to use Mysql queries in ROR

1)ruby script/generate controller Buy index2) You can create a class method in the model,\app\models\products . rb, named, say,

return_products, like this:class product < A ctiveRecord::Basedef self . return_products

find(:all,:order => name description ,:conditions =>price

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There are actually three ways to call find:

find(:id) Finds a record by IDfind(:first) Finds the first recordfind(:all) Returns all the records in the

table

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Those other requirements are SQL-oriented; if you know SQL, here they are:

R uby SQL Information:conditions SQL code indicating a condition orconditions to match .

:group Specifies an attribute indicating how theresult should be grouped, making use of theSQL GROUP BY clause.

:include Specifies associations to be includedusing SQL LEFT OUTER JOINs.

:joins Specifies additional SQL joins .

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:limit Specifies an integer setting the upper limitof the number of rows to be returned .

:offset Specifies an integer indicating the offsetfrom where the rows should be returned .

:order Lets you specify the fields to set the orderof returned records .

:readonly Marks the returned records read-only .

:select A SQL SELECT statement, as in SELECT *

FROM items .

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To start the process of displaying the items forsale when the buy controller s index action is

called, you call return_items in the indexaction:class BuyController < A pplicationController

def index@items = Item . return_itemsendend

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Show Database Items in a Web Page

The Store

Buy From Our Store!

Welcome to the store .
Please buy a lot of items, hankyou .

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