Summary of JavaScript basic functions_Basic knowledge

Here is a summary of some basic JavaScript functions for you, which are commonly used and practical. Sorting it out will also help everyone better understand javascript.

Copy code The code is as follows: /*Create functions and literal functions*/ /* function add(){ alert("Function created successfully") }; var testfunction=function(){ alert("This is an anonymous function"); }; add(); //Call function testfunction();//Call literal function */ /* var testobj=new Object(); //Create object TestObj.run = Function () {// Create a method to the object alert("This is a method inside the object"); }; testobj.run(); // Call the object’s method */ /*Create function object*/ /* function ball(){ } ball.name1="testing"; //Create attributes for the function object alert(ball.name1); //Access function attributes alert(typeof ball) */ /*Reference of function*/ /* function myFunction(message){ alert(message); } var ptr=myFunction; // Pass the reference of the function to the variable ptr("Testing"); //Variable call function */ /* Pass the reference of the function to the object*/ /* function sayName(name1){ alert(name1); } var obj1=new Object(); var obj2=new Object(); var obj3=new Object(); obj1.sayMyName=sayName; // Pass the reference to the variable of the object to form the method of the object obj2.sayMyName=sayName; obj3.sayMyName=sayName; obj1.sayMyName("Zhang San") //Call the object's method obj2.sayMyName("李思"); obj3.sayMyName("王五") */ /* function add(){ } add.message="chaiyesong" var ptr1=add; var ptr2=add; alert(ptr1.message); alert(ptr2.message) add.message="123"; alert(ptr1.message) alert(ptr2.message) */ /*Reference points to another variable*/ /* function add(){ alert("one"); } var ptr=add; ptr=function(){ //Created another function called myFunctionPtr instead of modifying it alert("ptr") } add=function(){ //The reference points to another function, and the reference of the function is modified alert("two") } add() ptr() */ /*Create function object*/ /* Function Ball(message){ alert(message) } var ball0=new Ball("testing") ball0.name1="ball-0" alert(ball0.name1) Function Ball(message){ alert(message) } var ball0=new Object() ball0.constuct=Ball; // Point the function reference to the constructor of an object ball0.constuct("ceshiceshiceshi") //This function is executed by the constructor of this object ball0.name1="tesing" alert(ball0.name1) function Test(){ } alert(Test.prototype) //Shared attributes */ /*Add shared attributes*/ /* function Fish(naem1,color1){ This.name1=naem1 This.color1=color1 } Fish.prototype.LivesIn="water" //Add shared attributes Fish.prototype.price=20 var fish1=new Fish("mackrel","gray") var fish2=new Fish("goldfish","orange"); var fish3=new Fish("salmon", "white"); for (var i=1; i { var fish=eval("fish" i); // I just get the pointer to the fish alert(fish.name1 "," fish.color1 "," fish.LivesIn "," fish.price); } */ /* function Employee(name, salary) { This.name=name; This.salary=salary; } Employee.prototype.getSalary=function getSalaryFunction() { return this.salary; } Employee.prototype.addSalary=function addSalaryFunction(addition) { This.salary=this.salary addition; } var boss1=new Employee("Joan", 200000); var boss2=new Employee("Kim", 100000); var boss3=new Employee("Sam", 150000); alert(boss1.getSalary()); // Output 200000 alert(boss2.getSalary()); // Output 100000 alert(boss3.getSalary()); // Output 150000 */ /*Anonymous function*/ /* (function(x,y){ alert(x y) })(2,3)//The ability of this function to execute itself */ /*Execute and call the function*/ /* var f1=function(){ return "testing" } alert(f1()) */ /*Give the result of self-execution to the variable*/ /* var f2=function(){ Return "ok" }() alert(f2) */ // ( // function(){ // alert("fa") // ) /* function box(){ var user='Tt' return function(){ return user; } } alert(box()()) //Call the embedded function */ // var b=box() // alert(b()) /*Automatic addition through closure function*/ /* function box(){ var age=100 Return function () {// The call is actually this method, which realizes the time when the data stays in memory age return age; } } var b=box() alert(b()) alert(b()) alert(b()) */ /*Start version*/ /* function box(){ var arr=[] //Declare an array for (var i = 0; i arr[i]=function(){ // Just assign the function to each element through the loop return i; } return arr; //Return an array } var b=box() //Assign the returned array to b document.writeln("The length of the array is: " b.length " ") //Return the length of the array for (var i = 0; i document.writeln("The value returned by the anonymous function is:" b[i]() " ") //The value of each element when executing this function is 5, because the value of the last element is 5 }; */ /*Improved version*/ /* function box1() { var arr1 = []; for (var i = 0; i Arr1 [i] = (function (num) {// Self -executing, assigning the results of the function self -execution to each element return num; })(i); } return arr1; } var b1 = box1(); // Return array for (var i = 0; i document.writeln("The output result after improvement is: ") Document.writeln (b1 [i] "& lt; br /& gt;"); // The array returned here, just print it } */ //Beta version /* var testarr=[]; for (var i = 0; i testarr[i]=function(){ return i; } }; document.writeln("The length of the test board is: " testarr.length " ") for (var i = 0; i Document.writeln ("Test version" (i 1) "Testarr [i]" & lt; br /& gt; ") }; var aa=function(){ Return 3 } document.writeln("Results of beta version test" aa) */ /*Improved version 3*/ /* function box3() { var arr3= []; for (var i = 0; i arr3[i] = (function (num) { Return function () { Return num; } })(i);//The result of self-execution is assigned to each element. After the execution is completed, the result of its execution is assigned to each element } return arr3; } var b3= box3(); for (var i = 0; i document.writeln(b3[i]() " "); } */ /*JS function tutorial address: //http://www.cnblogs.com/ttcc/p/3763437.html*/ /*The object specified by this in the closure is window*/ /* var user='The Window00'; var obj={ user:'The Window001', getUserFunction:function(){ return function(){ return this.user; } } } document.writeln("Return the object specified by this" obj.getUserFunction()()) */ // function box(count1){ // for (var i = 0; i document.writeln(i); // } // var i=10 // box(2) /*After the closure is executed, the memory data will be cleared immediately*/ /* function box(count) { (function () { for (var i = 0; i } })(); document.writeln(i); } box(2); */ /*Access privacy attributes through closures*/ /* function Box() { var age = 100; function run() {//Private function return 'Running...'; } This.get = function () { //Public privileged method return age run(); }; } var box = new Box(); alert(box.get()); function Person(value) { var user = value; This.getUser = function () { return user; }; This.setUser = function (value) { user = value; }; } */ /*Single case mode*/ /* var box = function () { Var user = 'tt'; // Private variables function run() { Return 'During operation ...'; } return { Publicgo: function () {// The privilege method of foreign public interface Return user run(); } }; }(); alert(box.publicGo()); */ /*Single-case mode*/ /* function Desk() { //A function is defined } var box = function () { var user = 'TT'; var user = 'TT'; function run() { Return 'During operation ...'; } Var desk = new desk (); // instantiated custom objects desk.publicGo = function () { return user run(); }; return desk; }(); alert(box.publicGo()); */

The above is the basic JavaScript function compiled by me. Friends, please study it carefully. I hope you will like it

Summary of JavaScript basic functions_Basic knowledge

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