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Reset

A reset button on an HTML form. A reset button resets all elements in a form to their defaults.

Client-side object

Implemented in

JavaScript 1.0

JavaScript 1.1: added type property; added onBlur and onFocus event handlers; added blur and focus methods

JavaScript 1.2: added handleEvent method

Created by

The HTML INPUT tag, with "reset" as the value of the TYPE attribute. For a given form, the JavaScript runtime engine creates an appropriate Reset object and puts it in the elements array of the corresponding Form object. You access a Reset object by indexing this array. You can index the array either by number or, if supplied, by using the value of the NAME attribute.

Event handlers

Description

A Reset object on a form looks as follows:

A Reset object is a form element and must be defined within a FORM tag.

The reset button's onClick event handler cannot prevent a form from being reset; once the button is clicked, the reset cannot be canceled.

Property Summary

Property Description
form

Specifies the form containing the Reset object.

name

Reflects the NAME attribute.

type

Reflects the TYPE attribute.

value

Reflects the VALUE attribute.

Method Summary

Method Description
blur

Removes focus from the reset button.

click

Simulates a mouse-click on the reset button.

focus

Gives focus to the reset button.

handleEvent

Invokes the handler for the specified event.

In addition, this object inherits the watch and unwatch methods from Object.

Examples

Example 1. The following example displays a Text object with the default value "CA" and a reset button with the text "Clear Form" displayed on its face. If the user types a state abbreviation in the Text object and then clicks the Clear Form button, the original value of "CA" is restored.

<B>State: </B><INPUT TYPE="text" NAME="state" VALUE="CA" SIZE="2">
<P><INPUT TYPE="reset" VALUE="Clear Form">
Example 2. The following example displays two Text objects, a Select object, and three radio buttons; all of these objects have default values. The form also has a reset button with the text "Defaults" on its face. If the user changes the value of any of the objects and then clicks the Defaults button, the original values are restored.

<HTML>
<HEAD>
<TITLE>Reset object example</TITLE>
</HEAD>
<BODY>
<FORM NAME="form1">
<BR><B>City: </B><INPUT TYPE="text" NAME="city" VALUE="Santa Cruz" SIZE="20">
<B>State: </B><INPUT TYPE="text" NAME="state" VALUE="CA" SIZE="2">
<P><SELECT NAME="colorChoice">
   <OPTION SELECTED> Blue
   <OPTION> Yellow
   <OPTION> Green
   <OPTION> Red
</SELECT>
<P><INPUT TYPE="radio" NAME="musicChoice" VALUE="soul-and-r&b"
   CHECKED> Soul and R&B
<BR><INPUT TYPE="radio" NAME="musicChoice" VALUE="jazz">
   Jazz
<BR><INPUT TYPE="radio" NAME="musicChoice" VALUE="classical">
   Classical
<P><INPUT TYPE="reset" VALUE="Defaults" NAME="reset1">
</FORM>
</BODY>
</HTML>

See also

Button, Form, onReset, Form.reset, Submit


blur

Removes focus from the reset button.

Method of

Reset

Implemented in

JavaScript 1.0

Syntax

blur()

Parameters

None

Examples

The following example removes focus from the reset button userReset:

userReset.blur()
This example assumes that the button is defined as

<INPUT TYPE="reset" NAME="userReset">

See also

Reset.focus


click

Simulates a mouse-click on the reset button, but does not trigger an object's onClick event handler.

Method of

Reset

Implemented in

JavaScript 1.0

Syntax

click()

Parameters

None


focus

Navigates to the reset button and gives it focus.

Method of

Reset

Implemented in

JavaScript 1.0

Syntax

focus()

Parameters

None

See also

Reset.blur


form

An object reference specifying the form containing the reset button.

Property of

Reset

Read-only

Implemented in

JavaScript 1.0

Description

Each form element has a form property that is a reference to the element's parent form. This property is especially useful in event handlers, where you might need to refer to another element on the current form.

See also

Form


handleEvent

Invokes the handler for the specified event.

Method of

Reset

Implemented in

JavaScript 1.2

Syntax

handleEvent(event)

Parameters

event

The name of an event for which the specified object has an event handler.


name

A string specifying the name of the reset button.

Property of

Reset

Implemented in

JavaScript 1.0

Security

JavaScript 1.1: This property is tainted by default. For information on data tainting, see the Client-Side JavaScript Guide.

Description

The value of the name property initially reflects the value of the NAME attribute. Changing the name property overrides this setting.

Do not confuse the name property with the label displayed on the reset button. The value property specifies the label for this button. The name property is not displayed on the screen; it is used to refer programmatically to the button.

If multiple objects on the same form have the same NAME attribute, an array of the given name is created automatically. Each element in the array represents an individual Form object. Elements are indexed in source order starting at 0. For example, if two Text elements and a Reset element on the same form have their NAME attribute set to "myField", an array with the elements myField[0], myField[1], and myField[2] is created. You need to be aware of this situation in your code and know whether myField refers to a single element or to an array of elements.

Examples

In the following example, the valueGetter function uses a for loop to iterate over the array of elements on the valueTest form. The msgWindow window displays the names of all the elements on the form:

newWindow=window.open("http://home.netscape.com")
function valueGetter() {
   var msgWindow=window.open("")
   for (var i = 0; i < newWindow.document.valueTest.elements.length; i++) {
      msgWindow.document.write(newWindow.document.valueTest.elements[i].name + "<BR>")
   }
}

See also

Reset.value


type

For all Reset objects, the value of the type property is "reset". This property specifies the form element's type.

Property of

Reset

Read-only

Implemented in

JavaScript 1.1

Examples

The following example writes the value of the type property for every element on a form.

for (var i = 0; i < document.form1.elements.length; i++) {
   document.writeln("<BR>type is " + document.form1.elements[i].type)
}

value

A string that reflects the reset button's VALUE attribute.

Property of

Reset

Read-only

Implemented in

JavaScript 1.0

Security

JavaScript 1.1: This property is tainted by default. For information on data tainting, see the Client-Side JavaScript Guide.

Description

This string is displayed on the face of the button. When a VALUE attribute is not specified in HTML, the value property is the string "Reset".

Do not confuse the value property with the name property. The name property is not displayed on the screen; it is used to refer programmatically to the button.

Examples

The following function evaluates the value property of a group of buttons and displays it in the msgWindow window:

function valueGetter() {
   var msgWindow=window.open("")
   msgWindow.document.write("submitButton.value is " +
      document.valueTest.submitButton.value + "<BR>")
   msgWindow.document.write("resetButton.value is " +
      document.valueTest.resetButton.value + "<BR>")
   msgWindow.document.write("helpButton.value is " +
      document.valueTest.helpButton.value + "<BR>")
   msgWindow.document.close()
}
This example displays the following values:

Query Submit
Reset
Help
The previous example assumes the buttons have been defined as follows:

<INPUT TYPE="submit" NAME="submitButton">
<INPUT TYPE="reset" NAME="resetButton">
<INPUT TYPE="button" NAME="helpButton" VALUE="Help">

See also

Reset.name


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Last Updated: 11/16/98 12:57:12

Copyright (c) 1998 Netscape Communications Corporation