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 remove a great deal of the need for
tedious scripting and styling that was required in HTML4.
Following is the simple example of using labels, radio buttons, and submit buttons −
NOTE − Try all the following example using latest version of Opera browser.
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.
Here is the simple syntax for placeholder attribute −
HTML5 introduced a new attribute called autofocus which would be used as follows −
The <input> element in HTML4
HTML4 input elements use the type attribute to specify the data type.HTML4 provides following types −| Type | Description |
|---|---|
| text | A free-form text field, nominally free of line breaks. |
| password | A free-form text field for sensitive information, nominally free of line breaks. |
| checkbox | A set of zero or more values from a predefined list. |
| radio | An enumerated value. |
| submit | A free form of button initiates form submission. |
| file | An arbitrary file with a MIME type and optionally a file name. |
| 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. |
| hidden | An arbitrary string that is not normally displayed to the user. |
| select | An enumerated value, much like the radio type. |
| textarea | A free-form text field, nominally with no line break restrictions. |
| button | A free form of button which can initiates any event related to button. |
... <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.
| S.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 This 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 This 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 This 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.
<!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>This will produce following result −
The placeholder attribute
HTML5 introduced a new attribute called placeholder. This attribute on <input> and <textarea> elements provides a hint to the user of what can be entered in the field. The place holder 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 Chrome browsers only.
<!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 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.
<!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>This will produce following result −
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