HTML Form Elements

This chapter describes all the different HTML form elements.

HTML Form Elements

The HTML <form> Elements

The HTML <form> element can contain one or more of the following form elements:

• <input>
• <label>
• <select>
• <textarea>
• <button>
• <fieldset>
• <legend>
• <datalist>
• <output>
• <option>
• <optgroup>

The <input> Element

One of the most used form element is the <input> element.

The <input> element can be displayed in several ways, depending on the type attribute.

Example:

<label for="fname">First name:</label>  
<input type="text"  id="fname"  name="fname">

All the different values of the type attribute are covered in the next chapter: HTML Input Types.

The <label> Element

The <label> element defines a label for several form elements.

The <label> element is useful for screen-reader users, because the screen-reader will read out loud the label when the user focus on the input element.

The <label> element also help users who have difficulty clicking on very small regions (such as radio buttons or checkboxes) - because when the user clicks the text within the <label> element, it toggles the radio button/checkbox.

The for attribute of the <label> tag should be equal to the id attribute of the <input> element to bind them together.

The <select> Element

The <select> element defines a drop-down list:

Example:

<label for="cars">Choose a car:</label>  
<select id="cars"  name="cars">  
	<option value="volvo">Volvo</option>  
	<option value="saab">Saab</option>  
	<option value="fiat">Fiat</option>  
	<option value="audi">Audi</option>  
</select>

The <option> elements defines an option that can be selected.

By default, the first item in the drop-down list is selected.

To define a pre-selected option, add the selected attribute to the option:

<option value="fiat"  selected>Fiat</option>

Visible Values:

Use the size attribute to specify the number of visible values:

<label for="cars">Choose a car:</label>  
<select id="cars"  name="cars"  size="3">  
	<option value="volvo">Volvo</option>  
	<option value="saab">Saab</option>  
	<option value="fiat">Fiat</option>  
	<option value="audi">Audi</option>  
</select>

Allow Multiple Selections:

Use the multiple attribute to allow the user to select more than one value:

Example:

<label for="cars">Choose a car:</label>  
<select id="cars"  name="cars"  size="4"  multiple>  
	<option value="volvo">Volvo</option>  
	<option value="saab">Saab</option>  
	<option value="fiat">Fiat</option>  
	<option value="audi">Audi</option>  
</select>

The <textarea> Element

The <textarea> element defines a multi-line input field (a text area):

Example:

<textarea name="message" rows="10" cols="30">  
The cat was playing in the garden.  
</textarea>

Note:

• The rows attribute specifies the visible number of lines in a text area.
• The cols attribute specifies the visible width of a text area.

You can also define the size of the text area by using CSS:

<textarea name="message"  style="width:200px; height:600px;">  
The cat was playing in the garden.  
</textarea>

The <button> Element

The <button> element defines a clickable button:

<button type="button"  onclick="alert('Hello World!')">Click Me!</button>

The <fieldset> and <legend> Elements

The <fieldset> element is used to group related data in a form.

The <legend> element defines a caption for the <fieldset> element.

<form action="/action_page.php">  
	<fieldset>  
		<legend>Personal Data:</legend>  
		<label for="fname">First name:</label><br>  
		<input type="text"  id="fname"  name="fname"  value="John"><br>  
		<label for="lname">Last name:</label><br>  
		<input type="text"  id="lname"  name="lname"  value="Doe"><br><br>  
		<input type="submit"  value="Submit">  
	</fieldset>  
</form>

Output:

The <datalist> Element

The <datalist> element specifies a list of pre-defined options for an <input> element.

Users will see a drop-down list of the pre-defined options as they input data.

The list attribute of the <input> element, must refer to the id attribute of the <datalist> element.

<form action="/action_page.php">  
	<input list="browsers">  
	<datalist id="browsers">  
		<option value="Internet Explorer">  
		<option value="Firefox">  
		<option value="Chrome">  
		<option value="Opera">  
		<option value="Safari">  
	</datalist>  
</form>

The <output> Element

The <output> element represents the result of a calculation (like one performed by a script).

Example: perform a calculation and show the result in an <output> element.

<form action="/action_page.php"  
oninput="x.value=parseInt(a.value)+parseInt(b.value)">  
0  
	<input type="range" id="a"  name="a"  value="50">  
	100 +  
	<input type="number"  id="b"  name="b"  value="50">  
	=  
	<output name="x"  for="a b"></output>  
	<br>
	<br>  
	<input type="submit">  
</form>