Xiaoqiang's HTML5 mobile development road (27) - JavaScript review 2-HTML Tutorial-php.cn

Home

Web Front-end

HTML Tutorial

Xiaoqiang's HTML5 mobile development road (27) - JavaScript review 2

黄舟

Feb 04, 2017 pm 02:16 PM

JavaScript object-oriented basic knowledge

1. How to define a class and use the following syntax to create a class

 function Person(name, age){ //习惯上第一个字母大写  
    //this修饰的变量称为属性  
    this.name = name;  
    this.age = age;  
    //如果属性值是一个函数，则这个属性就是一个方法  
    this.play = function(){  
        alert(&#39;play football...&#39;);  
    };  
}

2. How to create an instance of the class

var p = new Person(&#39;zs&#39;, 22);  
p.play();  
p.name;

3. Two other ways to create javascript objects

(1) First create an instance of the Object type, and then add new properties and methods

javascript is a Dynamic language, you can add new properties and methods to objects at runtime

var obj = new Object();  
obj.name = &#39;zs&#39;;  
obj.age = 22;  
obj.play = function(){  
    alert(&#39;play...&#39;);  
};

(2) Use "json" syntax

  var p = {&#39;name&#39;:&#39;zs&#39;,&#39;age&#39;:22};  
ar p = {&#39;name&#39;:&#39;zs&#39;,&#39;play&#39;:function(){  
alert(&#39;hello&#39;);  
};

var p = {name:&#39;zs&#39;,age:22,marrid:false};  
var p = {name:&#39;zs&#39;,play:function(){  
    alert(&#39;hello&#39;);  
}};

attribute value If it is a string, it must be enclosed in quotation marks (single and double)

The attribute value allows number, string, boolean, null, Object

var p = {name:&#39;zs&#39;,  
    address:{  
        city:&#39;beijing&#39;,  
        street:&#39;ca&#39;  
    }  
};

A complete example

<html>  
    <head>  
        <script>  
            function f1(){  
                //var p = {&#39;name&#39;:&#39;zs&#39;,&#39;age&#39;:22};  
                //var p = {name:&#39;zs&#39;,age:22,marrid:false};  
                var p = {name:&#39;zs&#39;,  
                    address:{  
                        city:&#39;beijing&#39;,  
                        street:&#39;ca&#39;  
                    }  
                };  
                //alert(p.name);  
                alert(p.address.city);  
            }  
            function f2(){  
                var arr = [  
                    {&#39;name&#39;:&#39;zs&#39;,&#39;age&#39;:22},  
                    {&#39;name&#39;:&#39;ls&#39;,&#39;age&#39;:32}  
                ];  
                alert(arr[1].name);  
            }  
        </script>  
    </head>  
    <body>  
        <input type="button" value="click me" onclick="f2();"/>  
    </body>  
</html>

The above is the content of Xiaoqiang’s HTML5 mobile development road (27) - JavaScript review 2. For more related content, please pay attention to the PHP Chinese website (www.php.cn)!

Statement

The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn

The Future of HTML, CSS, and JavaScript: Web Development TrendsApr 19, 2025 am 12:02 AM

The future trends of HTML are semantics and web components, the future trends of CSS are CSS-in-JS and CSSHoudini, and the future trends of JavaScript are WebAssembly and Serverless. 1. HTML semantics improve accessibility and SEO effects, and Web components improve development efficiency, but attention should be paid to browser compatibility. 2. CSS-in-JS enhances style management flexibility but may increase file size. CSSHoudini allows direct operation of CSS rendering. 3.WebAssembly optimizes browser application performance but has a steep learning curve, and Serverless simplifies development but requires optimization of cold start problems.

HTML: The Structure, CSS: The Style, JavaScript: The BehaviorApr 18, 2025 am 12:09 AM

The roles of HTML, CSS and JavaScript in web development are: 1. HTML defines the web page structure, 2. CSS controls the web page style, and 3. JavaScript adds dynamic behavior. Together, they build the framework, aesthetics and interactivity of modern websites.

The Future of HTML: Evolution and Trends in Web DesignApr 17, 2025 am 12:12 AM

The future of HTML is full of infinite possibilities. 1) New features and standards will include more semantic tags and the popularity of WebComponents. 2) The web design trend will continue to develop towards responsive and accessible design. 3) Performance optimization will improve the user experience through responsive image loading and lazy loading technologies.

HTML vs. CSS vs. JavaScript: A Comparative OverviewApr 16, 2025 am 12:04 AM

The roles of HTML, CSS and JavaScript in web development are: HTML is responsible for content structure, CSS is responsible for style, and JavaScript is responsible for dynamic behavior. 1. HTML defines the web page structure and content through tags to ensure semantics. 2. CSS controls the web page style through selectors and attributes to make it beautiful and easy to read. 3. JavaScript controls web page behavior through scripts to achieve dynamic and interactive functions.

HTML: Is It a Programming Language or Something Else?Apr 15, 2025 am 12:13 AM

HTMLisnotaprogramminglanguage;itisamarkuplanguage.1)HTMLstructuresandformatswebcontentusingtags.2)ItworkswithCSSforstylingandJavaScriptforinteractivity,enhancingwebdevelopment.

HTML: Building the Structure of Web PagesApr 14, 2025 am 12:14 AM

HTML is the cornerstone of building web page structure. 1. HTML defines the content structure and semantics, and uses, etc. tags. 2. Provide semantic markers, such as, etc., to improve SEO effect. 3. To realize user interaction through tags, pay attention to form verification. 4. Use advanced elements such as, combined with JavaScript to achieve dynamic effects. 5. Common errors include unclosed labels and unquoted attribute values, and verification tools are required. 6. Optimization strategies include reducing HTTP requests, compressing HTML, using semantic tags, etc.

From Text to Websites: The Power of HTMLApr 13, 2025 am 12:07 AM

HTML is a language used to build web pages, defining web page structure and content through tags and attributes. 1) HTML organizes document structure through tags, such as,. 2) The browser parses HTML to build the DOM and renders the web page. 3) New features of HTML5, such as, enhance multimedia functions. 4) Common errors include unclosed labels and unquoted attribute values. 5) Optimization suggestions include using semantic tags and reducing file size.

Understanding HTML, CSS, and JavaScript: A Beginner's GuideApr 12, 2025 am 12:02 AM

WebdevelopmentreliesonHTML,CSS,andJavaScript:1)HTMLstructurescontent,2)CSSstylesit,and3)JavaScriptaddsinteractivity,formingthebasisofmodernwebexperiences.

See all articles