alert() JavaScript window, OK , , confirm() prompt():
1. alert () (window. alert())
. , alert(), , , .
2. confirm ()
, confirm(), . ʻ, true, (Cancel), false. , .
3. prompt(, ___)
prompt , , . alertQ confirm() : , . , : (Cancel). , , , false. .
, window, , .
<!-- pr6: -->
<html> <head>
<title> </title>
<script type="text/javascript">
alert(" JavaScript alert()!");
confirm(" confirm, !");
prompt(" prompt(), ");
</script>
</head>
<body >
<P> <CENTER>
<H1 style="color:blue"> : alert(), confirm() prompt() </h1>
<HR><P><P>C </center>
</body>
</html>
, e .
, .
JavaScript Adobe DreamWeaver CS5 (JQuery API). Java JavaScript Eclipse Eclipse JSEclipse Aptana Studio.
JavaScript Adobe life, Dojo Toolkit, Extjs, jQuery, Mootools, Prototype, Qooxdoo (.).
JavaScript . : ; ; () ; undefined ; null - . : , . . , Number, String Boolean( ), . . , .
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JavaScript var, :
var x;//undefined -
:
x = "Sample string";
JavaScript , , . . , :
var man1 =10;
man1 = "Superman";
new:
var man2 = new String("Superman");
Javascript - , . , , . , , :
alert("Superman".length);
JavaScript , :
y = "Second string";
y , window . , .
. , . -:
var test = Boolean("Stroka") // true
var = Number("1234")
var z=String(x);
parseInt() parseFloat(). . toString () , .
var x=Number.toString()
var y=number.toString()
number Number, toString(). toFixed toExponential().
<!-- pr7: -->
<html> <head>
<title> </title>
</head>
<body >
<P> <CENTER>
<HR><P><P>C </center>
<script type="text/javascript">
var x=parseInt("35.55");
alert(2+2+ " "+25);//425
confirm(" x= " + x);//35
x=Number("25.5")+0.5; //26
prompt(" x= "+x);//26
</script>
</body>
</html>
JavaScript . 253 253, 1.7976 x 10308 2.2250 x 10-308.
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, 1.25e-05.
, x, , 0 9 A F.
, Web .
JavaScript : 0, 0 7.
, Infinity . . , , .
NaN (not a number). , NaN, . , NaN, isNaN(), true, ( ), false, NaN.
: Number.MAX_VALUE- , Number.MIN_VALUE- , Number.NaN - , Number.POSITIVE_INFINITY - , Number.NEGATIVE_INFINITY -
. , length ( ) , :
charAt(index: Number): String , ;
concat([string1: String [,... [, stringN: String]]]]): String ( +);
substr(start: Number [, length: Number]): String , ;
substring(start: Number, end: Number): String , , .
JavaScript , charAt() , SetcharAt() . (s1==s2), .
. JavaScript ( ): \n, \r, \t, \, \\, \xcode.
: true ; false . if. :
var d= true;
if (d) { alert(Hello, World!); }