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JSScript Microsoft Inc.
First, JavaScript basic syntax.
(a) Data type and variable type.
Data types: Integers, decimals, booleans, Strings, datetime, arrays ...
var a=5;a=a+5; 10
var b= "5"; b=b+5; 55
Cast:
parseint () ----coerced into integers
parsefloat ()-----forcibly converted to decimals
Cases:
<script language= "JavaScript" >
var a= "15169377135o";
var b=parseint (a);
alert (b);
</script>--------15169377135
<script language= "JavaScript" >
var a= "15169377135o1234";
var b=parseint (a);
alert (b);
</script>--------15169377135
<script language= "JavaScript" >
var a= "s15169377135";
var b=parseint (a);
alert (b);
</script>--------IsNaN
IsNaN ()--------Determine if it is a valid numeric type, not (true), yes (false)
Operator: (Arithmetic operator (7) relational operator (6) logical operator (3) other operator)
Statement: for ( var i=0,i<a.length,i++) {}
(b) Array data type [] array name =new data type [];
var array name = new Array ([length]);//"fake" array, length suggestions are not written.
a.length----Length
a[subscript] = value.
A[]
(three) functions
Function function name (formal parameter)
{
}
Function Showstr (a)
{
}
Two, DOM operation
Dom-document object Model document.
Linear model, tree-shaped model, mesh model
Window (browser)
History---forward retreat (historical)
Location---Address bar
Document----documents, HTML pages Head
Body
A,img,table,ul,ol .....
Status-----State Bar
An object--object the characteristics of a noun, a verb (verb ()) of the Act;
(a) window
1.alert ()
Window.alert ();
2.[var a =]window.confirm ("Can you run over the leopard?" ");
Cases:
<script language= "JavaScript" >
var a=window.confirm ("Can you run over a leopard?") ");
if (a==true)
{
Alert ("You are more animals than animals!") ");
}
Else
{
Alert ("You beast!" ");
}
</script>
Prompt (); --infrequently used, no need to remember, input
3.open ();
var retval = window.open (URL, name, features, replace);
Replace
An optional Boolean value. Specifies whether the URL loaded into the window creates a new entry in the window's browsing history or replaces the current entry in the browsing history. The following values are supported:
window.open ("Address", "_blank/_self", "new Window Features");
[var a =]window.open ("http://www.sina.com.cn");
Open the page in a new window and return to the new window. A is also a variable of window type.
var a=window.open ("http://www.sina.com.cn", "_blank", "width=200 height=200 top=0 left=0 toolbar=no");
4.close ();
Window.close ();
5.setTimeout ("code", number of milliseconds)
Executes the code one time after the specified number of milliseconds.
Cases:
<body>
<H1 id= "hh" ></body>
<script language= "JavaScript" >
function Showtime ()
{
var dt=new Date ();
document.getElementById ("hh"). Innerhtml=dt;
Window.settimeout ("Showtime ()", 1000);
}
Showtime ();
</script>
Schedules
Open the page, five seconds after the ad, and then 5 seconds ads off ************
var A;
function Openad ()
{
A = window.open ("http://www.sina.com.cn", "_blank", "width=200 height=200 toolbar=no top=0 left=0");
Window.settimeout ("Closead ()", 5000);
}
function Closead ()
{
A.close ();
}
Window.settimeout ("Openad ()", 5000);
6.setInterval ("code", number of milliseconds)
Executes code once every specified number of milliseconds.
Cases:
<body>
<H1 id= "hh" ></body>
<script language= "JavaScript" >
function Showtime ()
{
var dt=new Date ();
document.getElementById ("hh"). Innerhtml=dt;
}
Window.setinterval ("Showtime ()", 1000);
</script>
Schedules
Window.moveto (x, y);
Window.resizeto (width,height);
Window.scrollto (x, y);
Note: The full screen window is not visible.
(ii) Historical operations
Window.history.go (n); n is positive, forward; n is negative, backward;
(c) Address bar operations
var s=window.location.href; Get the address of the current page
Refresh the page regularly
function Showself ()
{
Window.location.href= "untitled-3.html";
}
Window.setinterval ("Showself ()", 1000);
(iv) document operations
Window.document
1. Find the Object
2. Operation Properties
3. Operation Style
4. Operation Contents
5. Operation elements.
JavaScript content Concatenation
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