eloquent javascript second edition

Objective:Although it is almost a load, but still on their own occupation-the front-end, vague, muddle. Therefore, does not seek the crane to stand alone group, but knows. From the JavaScript DOM Programming Art (2nd edition), start with a foundation, and at the same time, understand the history of industry development. More unknown so the insistence, less a trace of the pursuit of fame and profit.Clarify t

One1. Get formvar form = Document.queryselector (' #formId '); var form = document.forms["FormName"];2.button:submit commits and Form.submit () submissions in JavaScript code the subtle differences3. Two ways of repeating a formDisable the Submit button after the first time the form is submitted, or cancel subsequent form submission actions in the onsubmit handler (how do I cancel the doubt?). ）。JavaScript

I. Object-oriented technology in JavaScript (solving how to use the fatigue in JS programming)1. Examples of collection classesThe collection represents a non-repeating unordered collection. Two basic methods: A. Add to Collection B. Whether in the collection.　　　　Reference: p218 set.js2. Enumeration examplesEnumeration represents a limited set of values.　　　　Examples of PokerTwo. Standard conversion method1. toString (); Tolocalstring ();2. ValueOf ();

Learn the contents of chapters fourth and fifthGarbage collectionJavaScript has an automatic garbage collection mechanism, local variables exist only during function execution, and in this process, local variables are allocated space on the stack (or heap) memory to store their values. When the function is executed, the local variables do not exist, so they can release their memory for future use. There are two main types of garbage collection strategies:Tag cleanup: Most commonly used in

Chapter III Basic Concepts1. In JavaScript is case-sensitive, the first character is the letter _ or $, the other characters can try the number of letters _ or $, the naming format requirements are camel writing (the first letter lowercase, the remainder of each meaningful word beginning capital such as FontSize)2. Single-line comment//block-level comment */* Multiline content * * Do not use keywords and reserved words3. In

(Uniform Resource Identifiers, Universal Resource Identifiers) to be sent to the browser. where encodeURI () is used primarily for the entire URI, and encodeURIComponent () is used primarily to encode a segment of the URI. The difference is that encodeURI () does not encode special characters that are themselves URIs, such as colons, forward slashes, question marks, and well sizes, while encodeuricomponent () encodes any non-standard characters it discovers. The two methods corresponding to enc

regular expressions defined in literal form/* * Match all ". At", case insensitive */ var pattern4 =/\.at/gi;002 RegExp constructor to create a regular expression/* * Same as PATTERN1, but created using the constructor function */ var New RegExp ("[Bc]at", "I");ECMAScript 5 explicitly stipulates that the use of regular expression literals must be the same as calling the RegExp constructor directly, each time creating anCreate a new RegExp instance.5.5 Function typeThe function is actually an ob

constructorThe instanceof operator returns true if the variable is a given reference type (identified by its prototype chain) and an instance of the prototype chain is introduced in the 6th chapter. Take a look at the following example:Alert (person instanceof Object); is the variable person an object? Alert (colors instanceof Array); is the variable colors an array? Alert (pattern instanceof REGEXP); is the variable pattern a regexp?As a rule, all reference types have values that are instances

){ varPara = document.createelement ("P"); varTXT =document.createTextNode (Request.responsetext); Para.appendchild (TXT); document.getElementById (' New '). AppendChild (para); } }; Request.send (NULL); } Else{alert (' Sorry,your browser doesn\ ' t support XMLHttpRequest '); }}addloadevent (getnewcontent);When the page load is complete, the above code initiates a GET request to load the Exemple.txt fileRequest.open ()The onreadystatechange in the code

this optimal step size of the smaller array109 //var Steparr = [1031612713, 217378076, 45806244, 9651787, 2034035, 428481, 90358, 19001, 4025, 836, 182, 34, 9, 1]//for large The step selection of an array the vari = 0;111 varSteparrlength =steparr.length; the varLen =Array.Length;113 varLen2 = parseint (LEN/2); the the for(; i ) { the if(Steparr[i] >len2) {117 Continue;118 }119 - Stepsort (Steparr[i]);121 }122 123 //Sort a step124

meanings and uses in the JavaScript language, and these words, collectively called "Reserved Words", cannot be used as variable names. In addition, the names of existing JavaScript functions or methods cannot be used to name variables. Do not use words such as alert, Var, or if as the name of the variable.Sharing onload EventsSuppose I have two functions: Firstfunction and Secondfunction. What do I do if I

JavaScript code must be executed through the html/xhtml document, and the first way is to put the JS code between the to put the , allowing the browser to load the page fasterPS: Browser page load order: Please read this articleJS Note: 1,///2,/* 3, JS can be used JS allows programmers to directly assign values to variables without prior declaration, the most efficient declaration and assignment practices: var mood= "Happy", age=33;JS is a weakly typ

integer (depending on the case, usually 1) fromCharCode (), receives one or more character encodings, converts to strings, and performs the opposite operation with charCodeAt () URI (Universal Resource Identifier) Methods: Encodeuri,encodeuricomponent,decodeuri,decodeuricomponent, encoding and decoding, decoding methods can only identify their corresponding coding methods Eval (), converts the string parameter that is brought into the executable statement and inserts it into the current pos

method is actually a property, Just the value type of the attribute is a function, we also call it a method: Category Properties/Methods Description Property Constructor Point to the function used to create the current object Method hasOwnProperty (PropertyName) Checks whether the given property is in the current object instance propertyIsEnumerable (PropertyName) Checks whether a given property can be enumerated by

Sixth Chapter ObjectAn object can be considered an unordered collection of its properties, and each property is a name/value pair. JavaScript objects are dynamic, can be added or can be deleted, and can manipulate objects by reference, not by value. If the variable x is a reference to an object, execute the code var y=x, and the variable y will also point to the reference to the same object, not to the copy of the object, so modifying the object with

, this usage is not a good habit and is not recommended for everyone to use. Essentially, when you create an associative array, you create an array object's properties. In JavaScript, all variables are actually objects of some kind. For example, a Boolean value is an object of type Boolean. In the above example, you are actually adding the name, year, and living three properties to the lemon array. Ideally, you should not modify the properties of an a

1. Method borrowing is "inheritance", and the prototype method in one class is used in another class. p227 Generic Object2. Private state:"The variable is closed in an anonymous function to simulate the private variables", these "variables" can only be accessed by the instance method of the class; 3. Construct refactoring:4. Factory method5. Subclass: "Method Chain", "constructor chain", "combination"6.201508110842_ "JavaScript authoritative Guide (si

Chapter two uses JS in HTMLGenerally put "JavaScript Advanced Programming (Third Edition)" Reading notes

I. Classes and modules1. The implementation of the class is based on the prototype inheritance mechanism.Two. Classes and prototypesThree. Classes and constructors1. The constructor is used to initialize the newly created object.2. Use new, so the constructor simply initializes the object state.3. Building a constructor is defining the class, so the first letter is capitalized .4.Four. Identification of constructors and classesFive. Constrctor Properties1. The value of the constructor property i

This book is a very basic book, but for the first time in the front of me is a good book, the harvest is very big, some basic things understand more thoroughly.1.DOM is the abbreviation for the Document Object model, which is what JavaScript does with the DOM, or the operation of the node.2.js DOM, this is all objects, there are properties there are methods.The 3.document object has a Body property, so it can be written directly to Document.body witho