Other Objects in JavaScript_Basics

anchors[]; links[]; Link connection object
usage: document.anchors[[x]]; document.links[[x]]; ;
Document.anchors is an array , including all anchor tags in the document ( tags containing the name attribute), and a subscript is defined for each anchor tag starting from 0 according to the order in the document.
Document.links is also an array, containing all link tags in the document (including the tag of the href attribute and the tag has both name and href attributes, it is both an Anchor object and a Link object.
In IE, if you add the "id="..."" attribute to the tag, the object will be assigned an identity (ID). When calling this object, you only need to use "” That’s it. Many document components can use this method to assign IDs, but be careful that no two IDs are the same.
anchors and links are arrays and have array properties and methods. A single Anchor object has no properties; the properties of a single Link object are shown below.

Attributes
protocol; hostname; port; host; pathname; hash; search; href are the same as location objects.
target returns/specifies the target window (string) of the connection, which is the same as the target attribute in the tag.
Event
onclick; onmouseover; onmouseout; onmousedown; onmouseup

applets[] Java applet object It is an array that contains all Applet objects (Java applet) in the document. As an array, there are array properties and methods. Regarding the properties and methods of a single Applet object, I quote: "The Applet object inherits all public properties and methods of the Java applet." (English original sentence: The Applet object inherits all public properties of the Java applet./The Applet object inherits all public methods of the Java applet.) Because I hate Java applets, I am not interested in its "public" and "private" issues, so I did not discuss them.
embeds[] Plug-in object It is an array that contains all plug-ins ( tags) in the document. Because each plug-in is different, each Embed object also has different properties and methods.
forms[]; Form form object document.forms[] is an array that contains all the forms in the document (

). To reference a single form, you can use document.forms[x], but generally speaking, people will do this: add the "name="..."" attribute to the

tag, then directly use "document." can be quoted.

Attributes of the Form object
name returns the name of the form, which is the

attribute.
action returns/sets the submission address of the form, which is the

attribute.
method returns/sets the form submission method, which is the

attribute.
target returns/sets the window returned after the form is submitted, which is the

attribute.
encoding returns/sets the encoding method of form submission content, which is the

attribute.
length returns the number of elements contained in the form.
Method
reset() resets the form. This is the same as pressing the "reset" button.
submit() submits the form. This is the same as pressing the "Submit" button.
Event
onreset; onsubmit

The following from "Button" to "Textarea" are all element objects of the form.
Button button object is specified by "". To reference a Button object, you can use "..". refers to the value of the "name="..."" attribute in the tag. You can use this method to reference any form element.

Attribute
name Returns/sets the name of the element specified with .
value returns/sets the value of the element specified with .
form returns the form object containing this element.
Method
blur() removes focus from an object.
focus() gives the object focus.
click() simulates a mouse click on the object.
Event
onclick; onmousedown; onmouseup

Checkbox checkbox object specified by "".

Attribute
name Returns/sets the name of the element specified with .
value returns/sets the value of the element specified with .
form returns the form object containing this element.
checked returns/sets whether the checkbox object is checked. This is a boolean value.
defaultChecked returns/sets whether the checkbox object is checked by default. This is a boolean value.
Method
blur() removes focus from an object.
focus() gives the object focus.
click() simulates a mouse click on the object.
Event
onclick

elements[]; Element form element object .elements is an array that contains all the objects of the form. Generally we do not use this array, but directly reference each specific object.
Hidden Hidden objects are specified by "".

Attribute
name Returns/sets the name of the element specified with .
value returns/sets the value of the element specified with .
form returns the form object containing this element.

Password Password input area object is specified by "".

Attribute
name Returns/sets the name of the element specified with .
value returns/sets the current value of the password input area.
defaultValue returns the default value specified with .
form returns the form object containing this element.
Method
blur() removes focus from an object.
focus() gives the object focus.
select() selects all the text in the password input area.
Event
onchange

Radio radio field object specified by "". A group of Radio objects have a common name (name attribute), so document.formName.radioName becomes an array. To access a single Radio object use: document.formName.radioName[x].

Attributes of a single Radio object
name returns/sets the name of the element specified with .
value returns/sets the value of the element specified with .
form returns the form object containing this element.
checked returns/sets whether the radio field object is selected. This is a boolean value.
defaultChecked returns/sets whether the object is selected by default. This is a boolean value.
Method
blur() removes focus from an object.
focus() gives the object focus.
click() simulates a mouse click on the object.
Event
onclick

Reset reset button object specified by "". Because Reset is also a button, it also has properties and methods of Button objects. As for the "onclick" event, it is generally replaced by onreset of the Form object.
Select selection area (drop-down menu, list) object is specified by "".

Attribute
name Returns/sets the name of the element specified with .
length returns the number of options under the Select object.
selectedIndex returns the index of the selected option. This subscript is the position of the option in the options[] array. If the Select object allows multiple selections, returns the index of the first selected option.
form returns the form object containing this element.
Method
blur() removes focus from an object.
focus() gives the object focus.
Event
onchange

options[]; Option selection object options[] is an array that contains Option objects under the same Select object. Option objects are specified by "" under "". The properties of

options[] array
length; selectedIndex are the same as the properties of the same name of the Select object to which they belong.
Attributes of a single Option object
text returns/specifies the text displayed by the Option object
value returns/specifies the value of the Option object, consistent with .
index returns the index of the Option object. There is nothing to say about this, because in order to specify a specific Option object, you must first know the subscript of the object. This attribute seems to have no use.
selected returns/specifies whether the object is selected. By specifying true or false, the selected items can be changed dynamically.
defaultSelected returns whether the object is selected by default. true / false.

Submit submit button object is specified by ". Because Submit is also a button, it also has the properties and methods of Button object. As for the "onclick" event, it is generally replaced by onsubmit of the Form object.
Text text The box object is specified by "". The Password object is also a type of Text object, so all the properties, methods and events of the Password object are available in the Text area object. "Specify. All the properties, methods and events of the Textarea object are the same as the Text object, that is, the same as the Password object.
images[]; Image image object document.images[] is an array that contains all the images in the document (). To reference a single image, you can use document.images[x]. If a picture contains the "name" attribute, that is, a picture is defined in the format of "<br>", you can use " document.images['...']" method to reference pictures. In IE, if a picture contains the ID attribute, that is, a picture is defined in the format of "<img alt="Other Objects in JavaScript_Basics" >", it can be used directly "<img alt="Other Objects in JavaScript_Basics" >" to reference the image. <img alt="Other Objects in JavaScript_Basics" ><imageid>The attributes of a single Image object <br>name; src; lowsrc; width; height; vspace; hspace; border. These attributes are the same as the attributes of the same name in the <br> tag. Same. In Netscape, except for the src attribute, other attributes (almost all) cannot be changed. Even if they are changed, the effect will not be displayed in the document. The most useful of these attributes is src. By assigning a value to the src attribute. , you can change the image in real time. <br>Event<img alt="Other Objects in JavaScript_Basics" >onclick <br>Image object not displayed in the document<br>Image object not displayed in the document is defined with var statement: <br><br> var myImage = new Image(); or <br>var myImage = new Image(<br>); <br>Then the myImage variable can be treated like a normal Image object, but since it is not displayed in the document. , the following attributes: lowsrc, width, height, vspace, hspace, border are of no use. Generally, this kind of object has only one use: preloading the image, because when the src attribute of the object is assigned, the entire document. Reading and JavaScript execution are paused, allowing the browser to concentrate on reading images. After pre-reading the image, there is a copy of the image in the browser's cache. When it is time to actually put the image into the document, the image can be displayed immediately. There are often some image connections in today's web pages. When the mouse points to it, the image is changed to another image. They all pre-read the image first. <br>JavaScript example of pre-reading images<br><br>var imagePreload = new Image(); <br>imagePreload.src = '001.gif'; <br>imagePreload.src = '002.gif'; <br>imagePreload.src = '003.gif'; <br><br>The above example is suitable for pre-reading a small number of images. <br><br>function imagePreload() { <br> var imgPreload = new Image(); <br> for (i = 0; i imgPreload.src = arguments[i ]; <br> } } <br>imagePreload('001.gif', '002.gif', '003.gif', '004.gif', '005.gif'); <br><br>The above example is suitable for pre-reading a large number of pictures.</imageid>