Summary of functions in jquery 1

Welcome to visit my github:huanshen, have my source code analysis

1. Each

It's much like a for loop, but it's more useful, and you know it if you understand it.

//iterate over an array or object    //obj is an array or an object that needs to be traversed    //callback is a callback function that handles each element of an array/object, and its return value actually interrupts the process of looping    //args is an additional array of argumentseachfunction(obj, callback, args) {varvalue, I= 0, Length=Obj.length, IsArray=isarraylike (obj); //If args exists, the parameter passed in the callback is the Grgs,each loop number, which is determined by obj .        if(args) {if(IsArray) { for(; i < length; i++) {Value=callback.apply (obj[i], args); if(Value = = =false ) {                         Break; }                }            } Else {                 for(Iinchobj) {Value=callback.apply (obj[i], args); if(Value = = =false ) {                         Break; }                }            }        //A Special, fast, case for the most common use of each        //Note that the following is call, which is apply        //the second parameter of apply is passed in as an array, but when it is actually running,        //The passed-in array parameter becomes a form, not an array parameter}Else {            if(IsArray) { for(; i < length; i++) {Value=Callback.call (obj[i], I, obj[i]); if(Value = = =false ) {                         Break; }                }            } Else {                 for(Iinchobj) {Value=Callback.call (obj[i], I, obj[i]); if(Value = = =false ) {                         Break; }                }            }        }        returnobj; },

2.makeArray

Converts an array of classes object to a group. The merge function is used in the middle, the third function is visible, and there is a description.

//to convert a class array object to a group object    //This method is an internal methodMakearray:function(arr, results) {varret = Results | | []; if(Arr! =NULL ) {            //If arr is a class array object, call merge to return a value            //still not very understanding isarraylike and merge            if(Isarraylike (Object (arr))) {Jquery.merge (ret),typeofarr = = = "string"?[arr]: arr); } Else {            //if it is not an array, drop it at the end of the returned array            //equivalent to Ret.push (arr);Core_push.call (ret, arr); }        }        returnret; },

About the middle of the object () can look at the following results (temporarily not very clear specific role):

var str= "Tttt",        arr1=[1,2,3],        obj={1:0},        str2=Object (str);    Console.log (Object (str))//{0: "T", 1: "T", 2: "T", 3: "T", length:4, [[[Primitivevalue]]: "TTTT"}    Console.log (str2.length)//4    console.log (Object (arr1))//[1, 2, 3]    console.log (Object (obj))//{1:0}

3. Merge

You can merge two arrays or class array objects

//add attributes from second to first    //second can be an array or a class array object, or something that contains 0, 1 propertiesMergefunction(first, second) {varL =Second.length, I=First.length, J= 0; if(typeofL = = = "Number" ) {             for(; J < L; J + +) {first[i++ ] =second[J]; }        } Else {             while(Second[j]!==undefined) {first[I+ +] = second[J + + ]; }} first.length=i; returnFirst ; },

4. Map

function is similar to each, but there are different places, mainly in dealing with the third parameter.

Mapfunction(Elems, Callback, ARG) {varvalue, I= 0, Length=Elems.length, IsArray=Isarraylike (elems), ret= []; //Go through the array, translating each of the items to their        //if it is an array, isarray=true;        //is consistent with each passed in parameter order        if(IsArray) { for(; i < length; i++) {Value=callback (elems[i], I, ARG); if(Value! =NULL) {ret[ret.length]=value; }            }        //Go through every key on the object,        //if the object}Else {             for(IinchElems) {Value=callback (elems[i], I, ARG); if(Value! =NULL) {ret[ret.length]=value; }            }        }        //Flatten any nested arrays        returncore_concat.apply ([], ret); },

5. Proxy

Proxy (), accept a function, and return a new function, and the new function always maintains a specific context.

Proxyfunction(FN, context) {vartmp, args, proxy; if(typeofContext = = = "string") {tmp=fn[context]; Context=fn; FN=tmp; }        //Quick Check to determine if target are callable, in the spec        //This throws a TypeError, but we'll just return undefined.        if( !jquery.isfunction (FN)) {            returnundefined; }        //simulated bind        //If the parameter passed in is 2 extra, the extra parameter is converted to an array. args = Core_slice.call (arguments, 2 ); Proxy=function() {            //currying is used here.            returnFn.apply (Context | | This, Args.concat (core_slice.call (arguments)));        }; //Set the GUID of unique handler to the same of original handler, so it can be removedProxy.guid = Fn.guid = Fn.guid | | jquery.guid++; returnproxy; },

Currying is a technique that transforms a function that accepts multiple parameters into a function that takes a single parameter (the first parameter of the original function) and returns a new function that takes the remaining parameters and returns the result. Here's an example: you can see that the previous two parameters have no output, and the last parameter and the new parameter make up the array output. In the above is passed as a parameter in the proxy

function T (l,t,y) {        var args = [].slice.call (arguments, 2 );        Console.log (args)        function  t () {            console.log (Args.concat ([].slice.call (arguments)));        }         return t;    }     var tt=t (N/a);    TT ("T"); // [3, "T"]

Summary of functions in jquery 1