--- title: HTMLFormElement slug: Web/API/HTMLFormElement tags: - API - DOM - HTML - Interface - NeedsTranslation - Reference - TopicStub translation_of: Web/API/HTMLFormElement ---
The HTMLFormElement
interface provides methods to create and modify {{HTMLElement("form")}} elements.
{{InheritanceDiagram(600,120)}}
This interface also inherits properties from its parent, {{domxref("HTMLElement")}}.
long
reflecting the number of controls in the form.Named inputs are added to their owner form instance as properties, and can overwrite native properties if they share the same name (eg a form with an input named action
will have its action
property return that input instead of the form's {{ htmlattrxref("action", "form") }} HTML attribute).
This interface also inherits methods from its parent, {{domxref("HTMLElement")}}.
true
if the element's child controls are subject to constraint validation and satisfy those contraints; returns false
if some controls do not satisfy their constraints. Fires an event named {{event("invalid")}} at any control that does not satisfy its constraints; such controls are considered invalid if the event is not canceled. It is up to the programmer to decide how to respond to false
.true
if the element's child controls satisfy their validation constraints. When false
is returned, cancelable {{Event("invalid")}} events are fired for each invalid child and validation problems are reported to the user.off
or on
. The form will receive an event once the user has finished with the interface, the event will either be {{event("autocomplete")}} when the fields have been filled or {{event("autocompleteerror")}} when there was a problem. This method has been removed from Chrome and Firefox — see {{bug(1270740)}} for background information on why.Create a new form element, modify its attributes and submit it:
var f = document.createElement("form");// Create a form document.body.appendChild(f); // Add it to the document body f.action = "/cgi-bin/some.cgi"; // Add action and method attributes f.method = "POST" f.submit(); // Call the form's submit method
Extract information from a form element and set some of its attributes:
<form name="formA" id="formA" action="/cgi-bin/test" method="POST"> <p>Click "Info" for form details; "Set" to change settings.</p> <p> <input type="button" value="info" onclick="getFormInfo();"> <input type="button" value="set" onclick="setFormInfo(this.form);"> <input type="reset" value="reset"><br> <textarea id="tex" style="height:15em; width:20em"></textarea> </p> </form> <script type="text/javascript"> function getFormInfo(){ var info; var f = document.forms["formA"]; //Get a reference to the form via id. info = "elements: " + f.elements + "\n" + "length: " + f.length + "\n" + "name: " + f.name + "\n" + "charset: " + f.acceptCharset+ "\n" + "action: " + f.action + "\n" + "enctype: " + f.enctype + "\n" + "encoding: " + f.encoding + "\n" + "method: " + f.method + "\n" + "target: " + f.target; document.forms["formA"].elements['tex'].value = info; } function setFormInfo(f){ //Argument is a reference to the form. f.method = "GET"; f.action = "/cgi-bin/evil_executable.cgi"; f.name = "totally_new"; } </script>
Submit a form in a popup window:
<!doctype html> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /> <title>MDN Example</title> <script type="text/javascript"> function popupSend (oFormElement) { if (oFormElement.method && oFormElement.method.toLowerCase() !== "get") { console.error("This script supports the GET method only."); return; } var oField, sFieldType, nFile, sSearch = ""; for (var nItem = 0; nItem < oFormElement.elements.length; nItem++) { oField = oFormElement.elements[nItem]; if (!oField.hasAttribute("name")) { continue; } sFieldType = oField.nodeName.toUpperCase() === "INPUT" ? oField.getAttribute("type").toUpperCase() : "TEXT"; if (sFieldType === "FILE") { for (nFile = 0; nFile < oField.files.length; sSearch += "&" + escape(oField.name) + "=" + escape(oField.files[nFile++].name)); } else if ((sFieldType !== "RADIO" && sFieldType !== "CHECKBOX") || oField.checked) { sSearch += "&" + escape(oField.name) + "=" + escape(oField.value); } } open(oFormElement.action.replace(/(?:\?.*)?$/, sSearch.replace(/^&/, "?")), "submit-" + (oFormElement.name || Math.floor(Math.random() * 1e6)), "resizable=yes,scrollbars=yes,status=yes"); } </script> </head> <body> <form name="yourForm" action="test.php" method="get" onsubmit="popupSend(this); return false;"> <p>First name: <input type="text" name="firstname" /><br /> Last name: <input type="text" name="lastname" /><br /> Password: <input type="password" name="pwd" /><br /> <input type="radio" name="sex" value="male" /> Male <input type="radio" name="sex" value="female" /> Female</p> <p><input type="checkbox" name="vehicle" value="Bike" />I have a bike<br /> <input type="checkbox" name="vehicle" value="Car" />I have a car</p> <p><input type="submit" value="Submit" /></p> </form> </body> </html>
XMLHttpRequest
If you want to know how to serialize and submit a form using the {{domxref("XMLHttpRequest")}} API, please read this paragraph.
Specification | Status | Comment |
---|---|---|
{{SpecName('HTML WHATWG', "forms.html#the-form-element", "HTMLFormElement")}} | {{Spec2('HTML WHATWG')}} | The following method has been added: requestAutocomplete() . |
{{SpecName('HTML5 W3C', "forms.html#the-form-element", "HTMLFormElement")}} | {{Spec2('HTML5 W3C')}} | The elements properties returns an {{domxref("HTMLFormControlsCollection")}} instead of a raw {{domxref("HTMLCollection")}}. This is mainly a technical change. The following method has been added: checkValidity() . The following properties have been added: autocomplete , noValidate , and encoding . |
{{SpecName('DOM2 HTML', 'html.html#ID-40002357', 'HTMLFormElement')}} | {{Spec2('DOM2 HTML')}} | No change |
{{SpecName('DOM1', 'level-one-html.html#ID-40002357', 'HTMLFormElement')}} | {{Spec2('DOM1')}} | Initial definition |
{{CompatibilityTable}}
Feature | Chrome | Edge | Firefox (Gecko) | Internet Explorer | Opera | Safari (WebKit) |
---|---|---|---|---|---|---|
Basic support | {{CompatVersionUnknown}} | {{CompatVersionUnknown}} | {{CompatGeckoDesktop(1.0)}}[1] | {{CompatVersionUnknown}} | {{CompatVersionUnknown}} | {{CompatVersionUnknown}} |
Feature | Android | Edge | Firefox Mobile (Gecko) | IE Phone | Opera Mobile | Safari Mobile |
---|---|---|---|---|---|---|
Basic support | {{CompatVersionUnknown}} | {{CompatVersionUnknown}} | {{CompatGeckoMobile(1.0)}}[1] | {{CompatVersionUnknown}} | {{CompatVersionUnknown}} | {{CompatVersionUnknown}} |
[1] In Firefox 56, the implementation has been updated so that the action
property returns the correct form submission URL, as per spec ({{bug(1366361)}}).