jQuery1.6 type judgment implementation code_jquery

First define
global variable class2type = {};
rdigit = /d/, // Regularly determine whether it is a number
toString = Object.prototype.toString;
Define class2type through jQuery.each Attributes and values:

Copy code The code is as follows:

jQuery.each("Boolean Number String Function Array Date RegExp Object".split(" "), function(i, name) {
class2type[ "[object " name "]" ] = name.toLowerCase();
});
Type: function( obj ) {
return obj == null ?String( obj ) :class2type[ toString.call(obj) ] || "object";//Everything in js is an object, so you can use toString .call(obj) returns the corresponding object type
// If you use this method directly to determine the type, document.getElementById under IE is considered to be object, and other browsers consider it to be function
// If the value passed in If it is NaN, "number" will be returned
　}
isFunction: function( obj ) {return jQuery.type(obj) === "function";}//Under IE, if document.getElementById is passed in , the return is false, IE is object
isArray: Array.isArray || function( obj ) {return jQuery.type(obj) === "array";}//If the native Array has the isArray method Use Array.isArray, otherwise customize this method
isWindow: function( obj ) {return obj && typeof obj === "object" && "setInterval" in obj;}//Determine whether it is a window object
isNaN : function( obj ) {return obj == null || !rdigit.test( obj ) || isNaN( obj );}//
　isEmptyObject: function( obj ) {
for ( var name in obj ) {//The basis for judgment is whether the object has attributes or methods
return false;
}
return true;
}