


Solutions to common problems in JavaScript (garbled characters, IE cache, proxy)_javascript skills
Two commonly used methods to solve AJAX Chinese garbled characters
1. EncodeURI on the client side (utf-8 does not need to be done, the default), and convert iso-8859-1 encoding to utf-8 encoding on the server side
2. EncodeURI twice on the client side and convert it once on the server side.
The reason why the second method can solve the problem:
After two conversions, perform the first decoding in the first getparameter method. Because the solution is in English (the result after the first encode), there will be no problem; the second time using URLDecoder decode method, so this problem can be solved normally. It should be noted that the decoding format needs to be specified as "utf-8" in the decode method. Many Chinese platforms do not use utf-8 (I guess it is gb2312), so the default conversion of decode is not necessarily utf-8.
The reason why the client is encoded twice and decoded only once on the server is because of Tomcat. In order to make programming convenient for programmers (get and post use the same code), Tomcat will automatically decode the encoding of the post, so there is one less handwritten decoding statement on the server side. The reason why we need to perform encoding and decoding again is because the automatic decoding operation of Tomcat is not necessarily decoded according to the encoding we want, but the codes decoded for English and other characters are the same no matter what platform they are on, so it can be Tomcat automatically interprets the result of the first encoding, and then manually interprets the encodeURI code once to obtain the format you need.
Additional: Now I have observed the behavior of the browser again, and I feel that it is not the fault of Tomcat, because the Chinese displayed in the browser is not the encoded content. I am now confused about these encoding issues. I'm confused, I hope friends who know this knowledge can give me some advice!
Solving the IE cache problem
Add a timestamp and want to check it?
Solve the agency problem
Want to do this? Convert to $
Sample code:
function verify() {
//Method 1 to solve the Chinese garbled problem, the data sent from the page side is encoded as an encodeURI, and the server segment uses new String(old.getBytes("iso8859-1"), "UTF-8");
// Method 2 to solve the problem of Chinese garbled characters. The data sent from the page side is encoded twice as encodeURI. In the server segment, use URLDecoder.decode(old,"UTF-8")
var url = "AJAXServer?name=" encodeURI(encodeURI($ ("#userName").val()));
url = convertURL(url);
$.get(url,null,function(data){
$("#result"). html(data);
});
}
//Add a timestamp to the url address, fool the browser and not read the cache
function convertURL(url) {
// Get the timestamp
var timstamp = (new Date()).valueOf();
//Splice the timestamp information into the url
//url = "AJAXServer"
if (url. indexOf("?") >= 0) {
url = url "&t=" timstamp;
} else {
url = url "?t=" timstamp;
}
return url;
}

JavaScript's application in the real world includes front-end and back-end development. 1) Display front-end applications by building a TODO list application, involving DOM operations and event processing. 2) Build RESTfulAPI through Node.js and Express to demonstrate back-end applications.

The main uses of JavaScript in web development include client interaction, form verification and asynchronous communication. 1) Dynamic content update and user interaction through DOM operations; 2) Client verification is carried out before the user submits data to improve the user experience; 3) Refreshless communication with the server is achieved through AJAX technology.

Understanding how JavaScript engine works internally is important to developers because it helps write more efficient code and understand performance bottlenecks and optimization strategies. 1) The engine's workflow includes three stages: parsing, compiling and execution; 2) During the execution process, the engine will perform dynamic optimization, such as inline cache and hidden classes; 3) Best practices include avoiding global variables, optimizing loops, using const and lets, and avoiding excessive use of closures.

Python is more suitable for beginners, with a smooth learning curve and concise syntax; JavaScript is suitable for front-end development, with a steep learning curve and flexible syntax. 1. Python syntax is intuitive and suitable for data science and back-end development. 2. JavaScript is flexible and widely used in front-end and server-side programming.

Python and JavaScript have their own advantages and disadvantages in terms of community, libraries and resources. 1) The Python community is friendly and suitable for beginners, but the front-end development resources are not as rich as JavaScript. 2) Python is powerful in data science and machine learning libraries, while JavaScript is better in front-end development libraries and frameworks. 3) Both have rich learning resources, but Python is suitable for starting with official documents, while JavaScript is better with MDNWebDocs. The choice should be based on project needs and personal interests.

The shift from C/C to JavaScript requires adapting to dynamic typing, garbage collection and asynchronous programming. 1) C/C is a statically typed language that requires manual memory management, while JavaScript is dynamically typed and garbage collection is automatically processed. 2) C/C needs to be compiled into machine code, while JavaScript is an interpreted language. 3) JavaScript introduces concepts such as closures, prototype chains and Promise, which enhances flexibility and asynchronous programming capabilities.

Different JavaScript engines have different effects when parsing and executing JavaScript code, because the implementation principles and optimization strategies of each engine differ. 1. Lexical analysis: convert source code into lexical unit. 2. Grammar analysis: Generate an abstract syntax tree. 3. Optimization and compilation: Generate machine code through the JIT compiler. 4. Execute: Run the machine code. V8 engine optimizes through instant compilation and hidden class, SpiderMonkey uses a type inference system, resulting in different performance performance on the same code.

JavaScript's applications in the real world include server-side programming, mobile application development and Internet of Things control: 1. Server-side programming is realized through Node.js, suitable for high concurrent request processing. 2. Mobile application development is carried out through ReactNative and supports cross-platform deployment. 3. Used for IoT device control through Johnny-Five library, suitable for hardware interaction.


Hot AI Tools

Undresser.AI Undress
AI-powered app for creating realistic nude photos

AI Clothes Remover
Online AI tool for removing clothes from photos.

Undress AI Tool
Undress images for free

Clothoff.io
AI clothes remover

AI Hentai Generator
Generate AI Hentai for free.

Hot Article

Hot Tools

ZendStudio 13.5.1 Mac
Powerful PHP integrated development environment

Notepad++7.3.1
Easy-to-use and free code editor

mPDF
mPDF is a PHP library that can generate PDF files from UTF-8 encoded HTML. The original author, Ian Back, wrote mPDF to output PDF files "on the fly" from his website and handle different languages. It is slower than original scripts like HTML2FPDF and produces larger files when using Unicode fonts, but supports CSS styles etc. and has a lot of enhancements. Supports almost all languages, including RTL (Arabic and Hebrew) and CJK (Chinese, Japanese and Korean). Supports nested block-level elements (such as P, DIV),

EditPlus Chinese cracked version
Small size, syntax highlighting, does not support code prompt function

Dreamweaver CS6
Visual web development tools