When you reference the select tag either by name or id you can then get its value or text from whichever option is selected using JavaScript and can also get the selected value in code on the server by referencing the select by name …. Yes but the select is the field that gets passed to the server, not the individual options. Giving a name to individual options is meaningless. The tooltip is an enhancement. The placeholder attribute is a string that provides a brief hint to the user as to what kind of information is expected in the field.
It should be a word or short phrase that provides a hint as to the expected type of data, rather than an explanation or prompt. The text must not include carriage returns or line feeds. So for example if a field is expected to capture a user's first name, and its label is "First Name", a suitable placeholder might be "e. Note: The placeholder attribute is not as semantically useful as other ways to explain your form, and can cause unexpected technical issues with your content. See Labels for more information.
A Boolean attribute which, if present, indicates that the user should not be able to edit the value of the input. The readonly attribute is supported by the text , search , url , tel , email , date , month , week , time , datetime-local , number , and password input types. See the HTML attribute: readonly for more information. The required attribute is supported by text , search , url , tel , email , date , month , week , time , datetime-local , number , password , checkbox , radio , and file inputs.
Valid for email , password , tel , url and text input types only. Specifies how much of the input is shown. Basically creates same result as setting CSS width property with a few specialities.
The actual unit of the value depends on the input type. For password and text , it is a number of characters or em units with a default value of 20 , and for others, it is pixel s. CSS width takes precedence over size attribute. Valid for the image input button only, the src is string specifying the URL of the image file to display to represent the graphical submit button.
The value must be a positive number—integer or float—or the special value any , which means no stepping is implied, and any value is allowed barring other constraints, such as min and max. For 4. Note: When the data entered by the user doesn't adhere to the stepping configuration, the value is considered invalid in contraint validation and will match the :invalid pseudoclass.
Global attribute valid for all elements, including all the input types, an integer attribute indicating if the element can take input focus is focusable , if it should participate to sequential keyboard navigation.
As all input types except for input of type hidden are focusable, this attribute should not be used on form controls, because doing so would require the management of the focus order for all elements within the document with the risk of harming usability and accessibility if done incorrectly. Global attribute valid for all elements, including all input types, containing a text representing advisory information related to the element it belongs to. Such information can typically, but not necessarily, be presented to the user as a tooltip.
The title should NOT be used as the primary explanation of the purpose of the form control. See Labels below. A string specifying the type of control to render. For example, to create a checkbox, a value of checkbox is used.
If omitted or an unknown value is specified , the input type text is used, creating a plaintext input field. The input control's value. The value attribute is always optional, though should be considered mandatory for checkbox , radio , and hidden. Valid for the image input button only, the width is the width of the image file to display to represent the graphical submit button.
The following non-standard attributes are also available on some browsers. As a general rule, you should avoid using them unless it can't be helped. A Safari extension, the autocorrect attribute is a string which indicates whether or not to activate automatic correction while the user is editing this field. Permitted values are:. Enable automatic correction of typos, as well as processing of text substitutions if any are configured.
As the user edits the value of the field, the user agent sends search events to the HTMLInputElement object representing the search box.
This allows your code to update the search results in real time as the user edits the search. If incremental is not specified, the search event is only sent when the user explicitly initiates a search such as by pressing the Enter or Return key while editing the field.
The search event is rate-limited so that it is not sent more frequently than an implementation-defined interval. A Mozilla extension, supported by Firefox for Android, which provides a hint as to what sort of action will be taken if the user presses the Enter or Return key while editing the field.
This information is used to decide what kind of label to use on the Enter key on the virtual keyboard. Note: This has been standardized as the global attribute enterkeyhint , but is not yet widely implemented.
To see the status of the change being implemented in Firefox, see bug Permitted values are: go , done , next , search , and send. The browser decides, using this hint, what label to put on the enter key. Values include horizontal , meaning the range is rendered horizontally, and vertical , where the range is rendered vertically.
The value must be a non-negative decimal number. If not provided, or an invalid value is given, the browser's default maximum number of entries is used. The Boolean webkitdirectory attribute, if present, indicates that only directories should be available to be selected by the user in the file picker interface. Though originally implemented only for WebKit-based browsers, webkitdirectory is also usable in Microsoft Edge as well as Firefox 50 and later.
However, even though it has relatively broad support, it is still not standard and should not be used unless you have no alternative. Immediately runs the validity check on the element, triggering the document to fire the invalid event at the element if the value isn't valid. Returns true if the element's value passes validity checks; otherwise, returns false. For elements with no selectable text content such as a visual color picker or calendar date input , this method does nothing.
Sets the contents of the specified range of characters in the input element to a given string. A selectMode parameter is available to allow controlling how the existing content is affected. Selects the specified range of characters within a textual input element. Does nothing for inputs which aren't presented as text input fields.
Inputs, being replaced elements, have a few features not applicable to non form elements. The input element can also be targeted by type with attribute selectors. There are some properties that are especially useful as well.
We can style a checkbox label based on whether the checkbox is checked or not. We haven't applied any styles if the input is not checked. It is possible to target different types of form controls based on their type using attribute selectors. CSS attribute selectors match elements based on either just the presence of a attribute or the value of a given attribute.
By default, the appearance of placeholder text is a translucent or light gray. The ::placeholder pseudo-element is the input's placeholder text. It can be styled with a limited subset of CSS properties. Only the subset of CSS properties that apply to the ::first-line pseudo-element can be used in a rule using ::placeholder in its selector.
The appearance property enables the displaying of almost any element as a platform-native style based on the operating system's theme as well as the removal of any platform-native styling with the none value. A property specific to text entry-related elements is the CSS caret-color property, which lets you set the color used to draw the text input caret:.
When it is, the position and size of the element's size and positioning within its frame can be adjusted using the CSS object-position and object-fit properties. In addition to an accessible name, the label provides a larger 'hit' area for mouse and touch screen users to click on or touch.
If you use plain text to "label" your input, this won't happen. Having the prompt part of the activation area for the input is helpful for people with motor control conditions. As web developers, it's important that we never assume that people will know all the things that we know. The placeholder should never be required to understand your forms.
It is not a label, and should not be used as a substitute, because it isn't. The placeholder is used to provide a hint as to what an inputted value should look like, not an explanation or prompt. Not only is the placeholder not accessible to screen readers, but once the user enters any text into the form control, or if the form control already has a value, the placeholder disappears.
Browsers with automatic page translation features may skip over attributes when translating, meaning the placeholder may not get translated. Note: Don't use the placeholder attribute if you can avoid it. Warning: Client-side validation is useful, but it does not guarantee that the server will receive valid data.
If the data must be in a specific format, always verify it also on the server-side, and return a HTTP response if the format is invalid. In addition to using CSS to style inputs based on the :valid or :invalid UI states based on the current state of each input, as noted in the UI pseudo-classes section above, the browser provides for client-side validation on attempted form submission.
On form submission, if there is a form control that fails constraint validation, supporting browsers will display an error message on the first invalid form control; displaying a default message based on the error type, or a message set by you. Some input types and other attributes place limits on what values are valid for a given input.
Several errors could occur, including a rangeUnderflow error if the value is less than 2, rangeOverflow if greater than 10, stepMismatch if the value is a number between 2 and 10, but not an even integer does not match the requirements of the step attribute , or typeMismatch if the value is not a number.
For the input types whose domain of possible values is periodic that is, at the highest possible value, the values wrap back around to the beginning rather than ending , it's possible for the values of the max and min properties to be reversed, which indicates that the range of permitted values starts at min , wraps around to the lowest possible value, then continues on until max is reached.
This is particularly useful for dates and times, such as when you want to allow the range to be from 8 PM to 8 AM:. Specific attributes and their values can lead to a specific error ValidityState :. If a form control doesn't have the required attribute, no value, or an empty string, is not invalid.
Even if the above attributes are present, with the exception of required , and empty string will not lead to an error. We can set limits on what values we accept, and supporting browsers will natively validate these form values and alert the user if there is a mistake when the form is submitted. In addition to the errors described in the table above, the validityState interface contains the badInput , valid , and customError boolean readonly properties.
The validity object includes:. For each of these Boolean properties, a value of true indicates that the specified reason validation may have failed is true, with the exception of the valid property, which is true if the element's value obeys all constraints. If there is an error, supporting browsers will both alert the user and prevent the form from being submitted.
A word of caution: if a custom error is set to a truthy value anything other than the empty string or null , the form will be prevented from being submitted. If there is no custom error message, and none of the other properties return true, valid will be true, and the form can be submitted.
Get access to thousands of hours of content and a supportive community. Start your free trial today. I don't understand the difference between the two. Don't they both have something to do with what goes back to the server. The value attribute is what is going to get sent back to the server.
For instance you can set the value of an input field in the html code, which is helpful for hidden or disabled inputs. The name attribute is how you reference the input, once the value from the input gets sent back to the server.
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