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Password

A text field on an HTML form that conceals its value by displaying asterisks (*). When the user enters text into the field, asterisks (*) hide entries from view.

Client-side object

Implemented in

JavaScript 1.0

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

JavaScript 1.2: added handleEvent method.

Created by

The HTML INPUT tag, with "password" as the value of the TYPE attribute. For a given form, the JavaScript runtime engine creates appropriate Password objects and puts these objects in the elements array of the corresponding Form object. You access a Password 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 Password object on a form looks as follows:

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

Security

JavaScript 1.1: If a user interactively modifies the value in a password field, you cannot evaluate it accurately unless data tainting is enabled. For information on data tainting, see the Client-Side JavaScript Guide.

Property Summary

Property Description
defaultValue

Reflects the VALUE attribute.

form

Specifies the form containing the Password object.

name

Reflects the NAME attribute.

type

Reflects the TYPE attribute.

value

Reflects the current value of the Password object's field.

Method Summary

Method Description
blur

Removes focus from the object.

focus

Gives focus to the object.

handleEvent

Invokes the handler for the specified event.

select

Selects the input area of the object.

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

Examples

The following example creates a Password object with no default value:

<B>Password:</B> 
<INPUT TYPE="password" NAME="password" VALUE="" SIZE=25>

See also

Form, Text


blur

Removes focus from the object.

Method of

Password

Implemented in

JavaScript 1.0

Syntax

blur()

Parameters

None

Examples

The following example removes focus from the password element userPass:

userPass.blur()
This example assumes that the password is defined as

<INPUT TYPE="password" NAME="userPass">

See also

Password.focus, Password.select


defaultValue

A string indicating the default value of a Password object.

Property of

Password

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 initial value of defaultValue is null (for security reasons), regardless of the value of the VALUE attribute.

Setting defaultValue programmatically overrides the initial setting. If you programmatically set defaultValue for the Password object and then evaluate it, JavaScript returns the current value.

You can set the defaultValue property at any time. The display of the related object does not update when you set the defaultValue property, only when you set the value property.

See also

Password.value


focus

Gives focus to the password object.

Method of

Password

Implemented in

JavaScript 1.0

Syntax

focus()

Parameters

None

Description

Use the focus method to navigate to the password field and give it focus. You can then either programmatically enter a value in the field or let the user enter a value.

Examples

In the following example, the checkPassword function confirms that a user has entered a valid password. If the password is not valid, the focus method returns focus to the Password object and the select method highlights it so the user can reenter the password.

function checkPassword(userPass) {
   if (badPassword) {
      alert("Please enter your password again.")
      userPass.focus()
      userPass.select()
   }
}
This example assumes that the Password object is defined as

<INPUT TYPE="password" NAME="userPass">

See also

Password.blur, Password.select


form

An object reference specifying the form containing this object.

Property of

Password

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.


handleEvent

Invokes the handler for the specified event.

Method of

Password

Implemented in

JavaScript 1.2

Syntax

handleEvent(event)

Parameters

event

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

Description

For information on handling events, see the Client-Side JavaScript Guide.


name

A string specifying the name of this object.

Property of

Password

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 name property initially reflects the value of the NAME attribute. Changing the name property overrides this setting. The name property is not displayed on-screen; it is used to refer to the objects programmatically.

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 Password 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>")
   }
}

select

Selects the input area of the password field.

Method of

Password

Implemented in

JavaScript 1.0

Syntax

select()

Parameters

None

Description

Use the select method to highlight the input area of the password field. You can use the select method with the focus method to highlight a field and position the cursor for a user response.

Examples

In the following example, the checkPassword function confirms that a user has entered a valid password. If the password is not valid, the select method highlights the password field and the focus method returns focus to it so the user can reenter the password.

function checkPassword(userPass) {
   if (badPassword) {
      alert("Please enter your password again.")
      userPass.focus()
      userPass.select()
   }
}
This example assumes that the password is defined as

<INPUT TYPE="password" NAME="userPass">

See also

Password.blur, Password.focus


type

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

Property of

Password

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 initially reflects the VALUE attribute.

Property of

Password

Implemented in

JavaScript 1.0

Security

JavaScript 1.1: This property is tainted by default. If you programmatically set the value property and then evaluate it, JavaScript returns the current value. If a user interactively modifies the value in the password field, you cannot evaluate it accurately unless data tainting is enabled. For information on data tainting, see the Client-Side JavaScript Guide.

Description

This string is represented by asterisks in the Password object field. The value of this property changes when a user or a program modifies the field, but the value is always displayed as asterisks.

See also

Password.defaultValue


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Last Updated: 11/16/98 12:57:04

Copyright (c) 1998 Netscape Communications Corporation