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1. BooleanÖµ¡¢Êý×Ö¡¢×Ö·û´®µÄÔʼֵÊÇα¶ÔÏó£¬ÕâÒâζ×ÅËûÃǾßÓÐÊôÐԺͷ½·¨¡£
var test = "hello";
alert(test.length); //outputs "5"
2. javascript Ëù¶¨ÒåµÄËùÓжÔÏó¶¼ÓÐ toString() ·½·¨£¬²»¹ÜÊÇα¶ÔÏó»¹ÊÇÕæµÄ¶ÔÏó£¬Boolean µÄ toString() ·½·¨Ö»·µ»Ø “true” »òÕß“false”¡£
var test = false;
alert(test.toString()); //outputs "false"
3. parseInt() ºÍ parseFloat()
alert(parseInt("1234test")); //outputs "1234"
alert(parseInt("0xA")); //outputs "10"
alert(parseInt("22.1")); //outputs "22"
alert(parseInt("test")); //outputs "NaN"
4. String() ºÍ toString() ΨһµÄÇø±ðÔÚÓÚ¶Ô null »òÕß undefined ÖµµÄÇ¿ÖÆ×ª»»ÉÏ¡£
var test = String(null) //"null"
var test1 = null;
var test2 = test1.toString(); //»á²úÉú´íÎó
5. Object “Àà”¡£
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{
if(as_SourceString.match(/^13[0-9]{9}$/g)) return true; //ÊÖ»úºÅΪ13¿ªÍ·µÄ11λÊý×Ö
else if(as_SourceString.match(/^[0]{1}[0-9]{2,3}[2-8]{1}[0-9]{5,7}$/g)) return true;¡¡¡¡//СÁéͨΪ0¿ªÍ·µÄ3-4λµÄÇøºÅ£«²»ÒÔ1ºÍ9¿ªÍ·µÄ6£8λÊý×Ö
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var a = new Array();
var b = new Array(8);
var c =
new Array("first", "second", "third");
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var d = ["first",
"second", "third"];
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function CheckAll(form) {//ȫѡ
for (var i=0;i var e = form.elements[i];
if (e.name != 'chkall')
e.checked = form.chkall.checked;
}
}
function checkSelect()//ÅжÏÊÇ·ñÓÐÑ¡ ......
javascript¶ÔÏóÖ®——ÄÚÖöÔÏó“Math”
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¡¡¡¡alert(Math.min(1,2,3))¡¡¡¡//Êä³ö “1”
¡¡¡¡alert(Math.max(1,2,3))¡¡¡¡//Êä³ö &ldq ......