通常用typeof来判断js变量的类型，但很多时候仅仅typeof满足不了要求的。
我写了一个自定义函数来做这个事，判断的比较全面了。
New
function
varType(v){
if
(
typeof
v===
"object"
){
if
(v===
null
)
return
'null'
;
if
(v.
constructor
)
return
(v.
constructor
.toString()).match(/(?:
)[\w\$]+/)[
0
];
if
(
typeof
typeof2===
'undefined'
&&
window
.execScript){
window
.execScript(
'Function vbsTypeName(o):vbsTypeName=TypeName(o):End
Function'
,
'vbscript'
);
window
.execScript(
'function typeof2(o){return vbsTypeName(o)}'
,
'jscript'
);
}
if
(
typeof
typeof2!==
'undefined'
){
return
typeof2(v);
}
return
"object"
;
}
return typeof
v;
}
//对于普通js常量和js对象，各浏览器是基本一致的
alert
(varType());
//undefined
alert
(varType(
100
));
//number
alert
(varType({}));
//Object
alert
(varType([]));
//Array
alert
(varType(/ /));
//RegExp
alert
(varType(
new
Date
()));
//Date
alert
(varType(
Date
));
//function
alert
(varType(
Object
));
//function
alert
(varType(
RegExp
));
//function
//对于DOM对象，各浏览器可能会有不同值
alert
(varType(
window
));
//IE:HTMLWindow2 FF:Window
alert
(varType(
document
));
//IE:HTMLDocument FF:HTMLDocument
alert
(varType(
document
.body));
//IE:HTMLBody FF:HTMLBodyElement
alert
(varType(
Option
));
//IE:Object FF:function
alert
(varType(
Image
));
//IE:Object FF:function
alert
(varType(
navigator
));
//IE:DispHTMLNavigator FF:Navigator
//以下几个只适用于IE，其他内核浏览器不支持
alert
(varType(
ActiveXObject
));
//IE:function
alert
(varType(
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312">
<title>php爱好者|phpfans.net|---判断远程图片是否存在，否则替换成默认图片</title>
</head>
<body>
<p>判断远程图片是否存在，不存在的话替换成默认的 ......
