JavaScript

Nonsense don't say much, directly to everyone paste JS code. The specific code looks like this: function Location () {}; Location.prototype.getLocation = function (callback) {var options = {enablehighaccuracy:true, maximumage:1000 };

Many web sites, when the mouse hovering over an element can pop up an information description layer, and this layer can follow the mouse movement, while the pop-up layer with arrows, this arrow pointing to the mouse hover elements, the following is

There are 5 simple data types in ECMAscript, also known as basic data types: Undefined, Null, Boolean, number, and string. There is also a complex data type--object. Undefined type When declaring a variable with VAR but not initializing it, the

In JavaScript, the most reliable way to determine what kind of built-in type an object's value belongs to is through the Object.prototype.toString method. var arr = []; Console.log (Object.prototype.toString.call (arr))//"[Object Array]"

Recommended reading: An array summation method of JavaScript learning notes Add, delete, change and check the array of JavaScript learning notes The sort () and reverse () methods are provided in JavaScript to reorder the array items. But many

The example of this article shares the HTML5 Canvas Province of China Map implementation method, for your reference, the specific contents are as follows 1. Data acquisitionMap needs provinces border coordinates, theoretically can use Baidu API

Reference types are important content in JavaScript. A reference type is a data structure that is used to organize data and functionality together. It describes the properties and methods of a class of objects. object is an underlying type, array is

Definition and usage of the split () method: The split () method splits the string into an array of strings using the substring of the string as a delimiter, and returns the array. Note: The substring as a delimiter does not become part of the

JavaScript is an object-based (object-based) language, and almost all of the things you encounter are objects. However, it is not a true object-oriented programming (OOP) language because its syntax has no class (class).So what should we do if we're

The Recent validation of JavaScript data types has a new understanding that can be judged so simple and comprehensive. We have customized methods such as Isstring,isnumber, IsDate, IsError, Isregexp, Isboolean, IsNull, isundefined, IsObject, etc.

Reader friends Good, I already have a general understanding of the role of JavaScript and some basic function declarations and variable declarations, today we will continue to explain the previous content, we will look at the logic of Javscript

first of all, let's say the difference between combo box and list box: The combo box includes the function of a list box and a text box Text boxes: Only data can be entered List box: Only data can be selected Combo box: Can input data, but also

Accessing local files is a headache for browser-based applications, and usually all we can do is upload files using tags. The implementation process is: When the file is selected, the Value property holds the name of the user-specified file, and

This article illustrates the way JavaScript implements the MD5 algorithm. Share to everyone for your reference, specific as follows: /** * * MD5 (message-digest algorithm) * http://www.webtoolkit.info/* **/var MD5 = function (string) {function

Let's start with a problem and delve into what is JavaScript object inheritance? For example, we have a constructor for an "animal" object. function animal () { This.type = ' animal '; } There is also a constructor for the "Cat"

Recently encountered a query page in a project where one of the criteria is to display the selected date, month, and number of weeks according to the selected year, such as a requirement. Search on the internet for a while, there are similar but not

Event objects are objects that are used to record information about events as they occur. Event objects are only generated when an event occurs, and can only be accessed internally by an event handler, and the event object is destroyed after all

First, Document.formName.item ("itemname") problem Problem description: Under IE, you can use Document.formName.item ("ItemName") or document.formName.elements ["ElementName"];firefox, You can only use the document.formname.elements["ElementName"].

There are two special values in JavaScript: undefined and null, which need to be noticed when comparing them. The undefined value is obtained when reading an unassigned variable or attempting to read an attribute that is not in an object.

Before the article also talked about the basic idea of dragging and dragging, the theory is there, that practice, can be applied to where? Below to bring you a drag-and-drop thought to write a small example, for everyone's reference, the general