HTML5 - Web Forms 2.0


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Web Forms 2.0 is an extension to the forms features found in HTML4. Form elements and attributes in HTML5 provide a greater degree of semantic mark-up than HTML4 and free us from a great deal of tedious scripting and styling that was required in HTML4.

The <input> element in HTML4

HTML4 input elements use the type attribute to specify the data type.HTML4 provides following types −

Sr.No. Type & Description
1

text

A free-form text field, nominally free of line breaks.

2

password

A free-form text field for sensitive information, nominally free of line breaks.

3

checkbox

A set of zero or more values from a predefined list.

4

radio

An enumerated value.

5

submit

A free form of button initiates form submission.

6

file

An arbitrary file with a MIME type and optionally a file name.

7

image

A coordinate, relative to a particular image's size, with the extra semantic that it must be the last value selected and initiates form submission.

8

hidden

An arbitrary string that is not normally displayed to the user.

9

select

An enumerated value, much like the radio type.

10

textarea

A free-form text field, nominally with no line break restrictions.

11

button

A free form of button which can initiates any event related to button.

Following is the simple example of using labels, radio buttons, and submit buttons −

... 
<form action = "http://example.com/cgiscript.pl" method = "post">  
   <p> 
      <label for = "firstname">first name: </label> 
      <input type = "text" id = "firstname"><br /> 
   
      <label for = "lastname">last name: </label> 
      <input type = "text" id = "lastname"><br /> 
   
      <label for = "email">email: </label> 
      <input type = "text" id = "email"><br> 
   
      <input type = "radio" name = "sex" value = "male"> Male<br> 
      <input type = "radio" name = "sex" value = "female"> Female<br> 
      <input type = "submit" value = "send"> <input type = "reset"> 
   </p> 
</form> 
 ... 

The <input> element in HTML5

Apart from the above-mentioned attributes, HTML5 input elements introduced several new values for the type attribute. These are listed below.

NOTE − Try all the following example using latest version of Opera browser.

Sr.No. Type & Description
1 datetime

A date and time (year, month, day, hour, minute, second, fractions of a second) encoded according to ISO 8601 with the time zone set to UTC.

2 datetime-local

A date and time (year, month, day, hour, minute, second, fractions of a second) encoded according to ISO 8601, with no time zone information.

3 date

A date (year, month, day) encoded according to ISO 8601.

4 month

A date consisting of a year and a month encoded according to ISO 8601.

5 week

A date consisting of a year and a week number encoded according to ISO 8601.

6 time

A time (hour, minute, seconds, fractional seconds) encoded according to ISO 8601.

7 number

It accepts only numerical value. The step attribute specifies the precision, defaulting to 1.

8 range

The range type is used for input fields that should contain a value from a range of numbers.

9 email

It accepts only email value. This type is used for input fields that should contain an e-mail address. If you try to submit a simple text, it forces to enter only email address in email@example.com format.

10 url

It accepts only URL value. This type is used for input fields that should contain a URL address. If you try to submit a simple text, it forces to enter only URL address either in http://www.example.com format or in http://example.com format.

The <output> element

HTML5 introduced a new element <output> which is used to represent the result of different types of output, such as output written by a script.

You can use the for attribute to specify a relationship between the output element and other elements in the document that affected the calculation (for example, as inputs or parameters). The value of the for attribute is a space-separated list of IDs of other elements.

Live Demo
<!DOCTYPE HTML>

<html>
   <head>
      <script type = "text/javascript">
         
         function showResult() {
            x = document.forms["myform"]["newinput"].value;
            document.forms["myform"]["result"].value = x;
         }
      </script>
   </head>
   
   <body>

      <form action = "/cgi-bin/html5.cgi" method = "get" name = "myform">
         Enter a value : <input type = "text" name = "newinput" />
         <input type = "button" value = "Result"  onclick = "showResult();" />
         <output name = "result"></output>
      </form>
		
   </body>
</html>

It will produce the following result −

The placeholder attribute

HTML5 introduced a new attribute called placeholder. This attribute on <input> and <textarea> elements provide a hint to the user of what can be entered in the field. The placeholder text must not contain carriage returns or line-feeds.

Here is the simple syntax for placeholder attribute −

<input type = "text" name = "search" placeholder = "search the web"/>

This attribute is supported by latest versions of Mozilla, Safari and Crome browsers only.

Live Demo
<!DOCTYPE HTML>

<html>
   <body>

      <form action = "/cgi-bin/html5.cgi" method = "get">
         Enter email : <input type = "email" name = "newinput" 
            placeholder = "email@example.com"/>
         <input type = "submit" value = "submit" />
      </form>

   </body>
</html>

This will produce the following result −

The autofocus attribute

This is a simple one-step pattern, easily programmed in JavaScript at the time of document load, automatically focus one particular form field.

HTML5 introduced a new attribute called autofocus which would be used as follows −

<input type = "text" name = "search" autofocus/>

This attribute is supported by latest versions of Mozilla, Safari and Chrome browsers only.

<!DOCTYPE HTML>

<html>
   <body>
   
      <form action = "/cgi-bin/html5.cgi" method = "get">
         Enter email : <input type = "text" name = "newinput" autofocus/>
         <p>Try to submit using Submit button</p>
         <input type = "submit" value = "submit" />
      </form>
      
   </body>
</html>

The required attribute

Now you do not need to have JavaScript for client-side validations like empty text box would never be submitted because HTML5 introduced a new attribute called required which would be used as follows and would insist to have a value −

<input type = "text" name = "search" required/>

This attribute is supported by latest versions of Mozilla, Safari and Chrome browsers only.

Live Demo
<!DOCTYPE HTML>

<html>
   <body>
   
      <form action = "/cgi-bin/html5.cgi" method = "get">
         Enter email : <input type = "text" name = "newinput" required/>
         <p>Try to submit using Submit button</p>
         <input type = "submit" value = "submit" />
      </form>
      
   </body>
</html>

It will produce the following result −



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