jquery Source Code Analysis: The jquery tool method detailed 2

jquery's Tool method, in fact, is static method, the source code is through the Extend method, these tools are added to the jquery constructor.

Jquery.extend ({

......

Type:function (obj) { //$.type (), Judging type
if (obj = = null) { //null,undefined
return String (obj); //return null,undefined string
} //core_tostring = {}.tostring
return typeof obj = = = "Object" | | typeof obj = = = "function"?
class2type[Core_tostring.call (obj)] | | "Object": //number,string and other packaging types, typeof judgment is an object, so enter into the ToString judgment, and eventually return number,string

typeof obj; //basic type, number,string directly with TypeOf.
},

Isplainobject:function (obj) { //To determine if an object argument is, {},new
if (Jquery.type (obj)!== "Object" | | obj.nodetype | | jquery.iswindow (obj)) {
return false; //dom nodes, window, and so on are objects, but not object arguments.
}

try { //window.location is Object,core_hasown is {}.hasownproperty (own property, not a prototype property)
if (Obj.constructor &&!core_hasown.call (Obj.constructor.prototype, "isprototypeof")) {
　　　　　　　　isPrototypeOf only exists in Object.prototype object, Core_hasown.call (Obj.constructor.prototype, "isprototypeof") The meaning of this sentence is: Obj.constructor.prototype whether there is isprototypeof attribute, from the above, only object.prototype have, so only object.prototype return true. For example, I pass in a person (constructor) whose prototype has no isprototypeof property, so it returns false. Person is not an object argument.

return false;
}//In Firefox version 20, if the operation Window.location.constructor multiple times, will be thrown wrong
} catch (e) {
return false;
}

return true;
},

Isemptyobject:function (obj) { //{},[], which Returns True if there are no properties and methods under the object itself. function person () {}; var person = new Person (), returns True

var name;
for (name in obj) { //The system comes with properties and methods that do not print for in.
return false;
}
return true;
},

Parsehtml:function (data, context, keepscripts) { //Parse string array node, for example: ' <li></li> ', [li element]

　　　　Keepscripts is true, can parse Script,false cannot parse script tag
if (!data | | typeof data!== "string") {
return null;
}
if (typeof context = = = = "Boolean") { //If there is not a second parameter
keepscripts = context;
context = false;
}
Context = Context | | Document

var parsed = rsingletag.exec (data), //If it is a single label "<li></li>"
Scripts =!keepscripts && [];

if (parsed) { //creates this element directly and then puts it in the array to return
return [Context.createelement (Parsed[1])];
}

parsed = Jquery.buildfragment ([data], context, scripts);

　　　　 If Keepscripts is false, an empty array scripts will be passed in, Buildfragment will determine if there is a script in data and, if so, put an empty array into [script] and return []. If Keepscripts is true, the incoming false,buildfragment does not change it, or false.

if (scripts) {
JQuery (Scripts). Remove (); //Remove script tag
}

return Jquery.merge ([], parsed.childnodes);
},//eval can parse the JSON string, any format can be, the danger increases. Json.parse () can only parse the standard JSON string, which performs better than Eval. 　

The Parsexml:function (data) { //Parse XML string is an XML document.
var XML, TMP;
if (!data | | typeof data!== "string") {
return null;
}

try {
TMP = new Domparser (); //ie6-8 use ActiveXObject to parse
XML = tmp.parsefromstring (data, "text/xml");

　　　　　　IE9, an error occurs if the XML string is not a normal XML tag. Other browsers will not error, generating PARSERERROR nodes in the returned XML document
} catch (e) {
xml = undefined;
}

if (!xml | | xml.getelementsbytagname ("parsererror"). Length) {
Jquery.error ("Invalid XML:" + data);
}
return XML;
},　

Globaleval:function (code) { //Changes the local variable to a global variable, for example: "Var a=1".
var script,
indirect = eval; //eval is both a keyword and a property under window. Directly write eval (code), the browser will be used as the JS keyword, error. So assigning a value, you'll see eval as the window's property.

Code = Jquery.trim (code); //code must be in the form of a string

if (code) {
if (Code.indexof ("use strict") = = = 1) { //Strict mode, eval cannot be used.
Script = document.createelement ("script");
Script.text = code;
Document.head.appendChild (script). Parentnode.removechild (script);
} else {
Indirect (code);
}
}
},　　

Camelcase:function (String) { //Goto hump, ie under:-ms-transform-Mstransform, while other-moz-transform-> moztransform, So first replace the-ms-with ms-, so that it will only turn into Mstransform,m not capitalized. and other browsers need to capitalize
Return String.Replace (Rmsprefix, "ms-"). Replace (Rdashalpha, fcamelcase);
},

......

})

Come on!

jquery Source Code Analysis: The jquery tool method detailed 2