fieldset | NN 6 IE 4 DOM 1 | ||
The fieldset object reflects the fieldset element. IE 5 for Macintosh implements the client and scroll measurement properties for this object. |
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HTML Equivalent | |||
<fieldset> |
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Object Model Reference | |||
[window.]document.getElementById("elementID")
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Object-Specific Properties | |||
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Object-Specific Methods | |||
None. |
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Object-Specific Event Handler Properties | |||
None. |
accessKey | NN n/a IE 4 DOM 1 |
Read/Write | |
This is single character key that either gives focus to an element (in some browsers) or activates a form control or link action. The browser and operating system determine if the user must press a modifier key (e.g., Ctrl, Alt, or Command) with the access key to activate the link. In Windows versions of IE 5 and later and Netscape 6, the Alt key is required and the key is not case-sensitive. For Macintosh versions of IE 5 and later and Netscape 6, the Ctrl modifier key is required to effect the action. |
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Although listed here as a widely shared property, that isn't strictly the case across all implementations. Netscape 6 (per the W3C DOM) recognizes this property only for the following elements: a, area, button, input, label, legend, and textarea. To this list, IE 4 adds applet, body, div, embed, isindex, marquee, object, select, span, table, and td (but removes label and legend). IE 5 adds every other renderable element, but with a caution. Except for input and other form-related elements, you must also assign a tabindex attribute or tabIndex property value to the IE 5 and later element (even if it's simply a value of zero for all) to let the accelerator key combination bring focus to the element. As of Version 7, Netscape does not alter UI behavior if a script changes the property's value. |
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Example | |
document.links[3].accessKey = "n"; |
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Value | |
Single alphanumeric (and punctuation) keyboard character. |
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Default | |
Empty string. |
align | NN n/a IE 4 DOM n/a |
Read/Write | |
Defines the horizontal alignment of the element within its surrounding container. In practice, this property has little effect on the fieldset object or its contents in IE 4. It behaves erratically in IE 6 for Windows, but responds as expected in IE 5 for Macintosh. |
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Example | |
document.getElementById("myFieldset").align = "center"; |
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Value | |
Any of the three horizontal alignment constants: center | left | right. |
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Default | |
left |
blur( ) | NN 2 IE 3 DOM 1 |
Removes focus from the current object, at which time the object's onblur event fires. Note that the range of elements capable of focus and blur (both the event and method) is limited in all browsers except for more recent versions of IE (see the shared tabindex attribute in Chapter 8). Most reliably for backward compatibility, apply the blur( ) method to blatantly focusable elements, such as text input and textarea elements. Assigning the attribute onfocus="this.blur( );" to a text input element, for instance, is a crude but effective backward-compatible way to largely disable a field for browsers that do not provide genuine element disabling. |
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Use blur( ) and focus( ) methods in moderation on the same page. You can inadvertently trigger endless loops of blurring and focusing if alert dialog boxes are involved along the way. Moreover, be aware that when you invoke the blur( ) method on one object, some other object (perhaps the window object) receives an onfocus event. |
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Parameters | |
None. |
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Returned Value | |
None. |
clientHeight, clientWidth | NN 7 IE 4 DOM n/a |
Read-only | |
Broadly speaking, these provide the height and width of the element's content, but with minor variations with respect to element padding among various operating system versions of IE and compatibility modes controlled by the DOCTYPE declaration. Not available for all element types in IE for Macintosh. For Netscape 7, values are zero except when an element's content overflows the viewable area, in which case the values reveal the dimensions of the viewable area (e.g., the browser window's content region for the document.body element). See the Section 9.2 at the beginning of this chapter for details. |
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Example | |
var midHeight = document.body.clientHeight/2; |
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Value | |
Integer pixel value. |
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Default | |
0 |
clientLeft, clientTop | NN n/a IE 4 DOM n/a |
Read-only | |
Broadly speaking, these provide the left and top coordinates of the element's content within the box that includes the element's padding, but with minor variations among various operating system versions of IE. Not available for all element types in IE for Macintosh. See the Section 9.2 at the beginning of this chapter for details. More useful information for inline element positioning generally comes from the offsetLeft and offsetTop properties (including Netscape 6). For CSS-positioned elements (including changing an element's position), use style object properties, such as left and top, and (in IE only) pixelLeft and pixelTop. |
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Value | |
Integer pixel value. |
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Default | |
0 |
filters[ ] | NN n/a IE 4 DOM n/a |
Returns an array of all filter objects contained by the current element. Applies only to the following element objects: bdo, body, button, div, fieldset, img, input, marquee, rt, ruby, span, table, td, textarea, and th. See the filter object for referencing syntax. |
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Value | |
Array of filter object references. |
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Default | |
Array of length zero. |
focus( ) | NN 2 IE 3 DOM 1 |
Gives focus from the current object, at which time the object's onfocus event fires. Note that the range of elements capable of focus and blur (both the event and method) is limited in all browsers except for more recent versions of IE (see the shared tabindex attribute in Chapter 8). Most reliably for backward compatibility, apply the focus( ) method to blatantly focusable elements, such as text input and textarea elements. |
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To give a text box focus and pre-select all the text in the box, use the sequence of focus( ) and select( ) methods on the element. If this sequence is to occur after windows change (such as after an alert dialog box closes), place the methods in a separate function, and invoke this function through the setTimeout( ) method following the alert( ) method for the dialog. This allows IE/Windows to sequence statement execution correctly. |
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Parameters | |
None. |
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Returned Value | |
None. |
form | NN 6 IE 5(Mac)/6(Win) DOM 1 |
Read-only | |
Returns a reference to the next outermost form element object in the document tree. Multiple fieldset element objects within the same form element reference the same form element object. |
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Example | |
var theForm = document.getElementById("myFieldset").form; |
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Value | |
Reference to a form element object. |
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Default | |
None. |
margin | NN n/a IE 5(Mac) DOM n/a |
Read-only | |
Returns an integer value, presumably of a margin setting. But the element does not feature a corresponding attribute. Ignore this property. |
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Value | |
Integer. |
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Default | |
7 |
scrollHeight, scrollWidth | NN 7 IE 4 DOM n/a |
Read-only | |
Originally implemented in IE 4 for elements that either scrolled or influenced an element's scroll (body, button, caption, div, fieldset, legend, marquee, and textarea), these properties return the pixel dimensions of an element, including elements that are larger than the viewable area in the browser window. This is in contrast to the clientHeight and clientWidth properties for scrollable elements, which return dimensions of only visible portions of the element. IE for the Macintosh, however, interprets the intent of the scroll- properties differently, returning the dimensions of the visible portion. |
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Starting in IE 5 for Windows, all HTML elements have these properties, and the values for nonscrolling elements are the same as the offsetHeight and offsetWidth properties. Netscape 7 implements these properties for all elements, returning the height and width of the element, whether or not it's in view. The important point is that for key elements, such as the body, the properties mean different things and can disrupt cross-platform operation. |
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Example | |
var midPoint = document.body.scrollHeight/2; |
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Value | |
Positive integer or zero. |
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Default | |
None. |
scrollLeft, scrollTop | NN 7 IE 4 DOM n/a |
Read/Write | |
Provide the distance in pixels between the actual left or top edge of the element's physical content and the left or top edge of the visible portion of the content. Setting these properties allows you to use a script to adjust the scrolling of content within a scrollable container, such as text in a textarea element or an entire document in the browser window or frame. When the content is not scrolled, both values are zero. Setting the scrollTop property to 15 scrolls the document upward by 15 pixels in the window; the scrollLeft property is unaffected unless explicitly changed. The property values change as the user adjusts the scrollbars. This is important for some event-driven positioning tasks in IE for Windows because the coordinate system for event offset measurements are with respect to the visible area of a page in the browser window. You must add document.body scrolling factors to align event coordinates with body content positions (see the element dragging example in Chapter 6). Starting with IE 5 for Windows, the scrollLeft and scrollTop properties are available for all HTML element objects, but values for unscrollable elements are zero. |
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Example | |
document.body.scrollTop = 40; |
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Value | |
Positive integer or zero. |
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Default | |
0 |
tabIndex | NN 6 IE 4 DOM 1 |
Read/Write | |
This is a number that indicates the sequence of this element within the tabbing order of all focusable elements in the document. Tabbing order follows a strict set of rules. Elements that have values other than zero assigned to their tabIndex properties are first in line when a user starts tabbing in a page. Focus starts with the element with the lowest tabIndex value and proceeds in order to the highest value, regardless of physical location on the page or in the document. If two elements have the same tabIndex values, the element that comes earlier in the document receives focus first. Next come all elements that either don't support the tabIndex property or have the value set to zero. These elements receive focus in the order in which they appear in the document. |
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The W3C DOM and Netscape 6 limit the tabIndex property to the following element objects: a, area, button, input, object, select, textarea. To this list, IE 4 adds applet, body, div, embed, isindex, marquee, span, table, and td. IE 5 adds every other renderable element. A negative value in IE (only) removes an element from tabbing order entirely. |
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Links and anchors cannot be tabbed to with the Mac version of IE 4, so the tabIndex property for a element objects is ignored in that version. |
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Example | |
document.getElementById("link3").tabIndex = 6; |
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Value | |
Integer. |
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Default | |
0 |