The difference between get method and post method in Ajax-PHP Tutorial-php.cn

Home

Backend Development

PHP Tutorial

The difference between get method and post method in Ajax

巴扎黑

Dec 01, 2016 am 11:45 AM

ajax

1. The basic difference between get() and post()

1.get adds the parameter data queue to the URL pointed to by the ACTION attribute of the submitted form. The value corresponds one-to-one to each field in the form, which can be seen in the URL. arrive. Post uses the HTTP post mechanism to place each field in the form and its content in the HTML HEADER and transmit it to the URL address pointed to by the ACTION attribute. Users cannot see this process.

2. For the get method, the server side uses Request.QueryString to obtain the value of the variable. For the post method, the server side uses Request.Form to obtain the submitted data. Parameters in both ways can be obtained using Request.

3. The amount of data transferred by get is small and cannot be larger than 2KB. The amount of data transmitted by post is relatively large and is generally unrestricted by default. But in theory, it varies from server to server.

4.get has very low security, while post has high security.

is different.

2. Talk about the difference between Ajax Get and Post

1. Get method
Use the get method to transmit simple data, but the size is generally limited to 1KB. The data is appended to the url and sent (http header transmission), that is That is, the browser appends each form field element and its data to the end of the resource path in the request line in the format of URL parameters. The most important thing is that it will be cached by the client's browser, so others can read the customer's data, such as account number and password, etc. from the browser's history. Therefore, in some cases, the get method can cause serious security issues.

Ajax send request: If it is a get request send (parameter) parameter: must be null or xhr.send();

It is not necessary to set xhr.setRequestHeader(header, value) for get request (Parameter); When the parameter is not empty, it will be automatically converted to the post request method. You can obtain the request method through the request.getMethod(); method

Example:

function getAjax(){ 
     //获取xhr对象
     var xhr = getXhr();
        //规定请求类型     
     xhr.open("get","main.jsp?username=123",true);
     xhr.onreadystatechange = function (){
          //判读是否处理完毕
          if(xhr.readyState==4){
               //判读服务器是否处理成功！
              if(xhr.status==200){
                    alert(xhr.responseText);
              }
          }
                } 
}

Be careful when using the get method

(1) For get For requests (or any involving url passing parameters), the passed parameters must first be processed by the

encodeURIComponent method. Example: var url = "update.php?username=" +encodeURIComponent(username) + "&content=" + encodeURIComponent

(content)+"&id=1" ;

2.Post method:

When using the POST method, the browser sends each form field element and its data to the Web server as the entity content of the HTTP message instead of Passed as a parameter of the URL address, the amount of data transmitted using the POST method is much larger than the amount of data transmitted using the GET method

Send request: If it is a post request send (parameter) parameter: the parameter can be null or

xhr .send()|send (with parameters) post request must set xhr.setRequestHeader(header,value) when passing value The Context-Type is application/x-www-form-

urlencode ensures that the server knows that there are parameter variables in the entity. Usually use the

SetRequestHeader("Context-Type","application/x-www-form-urlencoded of the XmlHttpRequest object ;"). Example:

xmlHttp.setRequestHeader("Content-Type","application/x-www-form-urlencoded")
(2). The parameters are key-value pairs with one-to-one name/value correspondence, and each pair of values uses an ampersand. Separate. For example, var name=abc&sex=man

&age=18 Note that var name=update.php?abc&sex=man&age=18 and var name=?abc&sex=man

&age=18 are both written incorrectly;

( 3). Parameters are sent in the Send (parameter) method, for example: xmlHttp.send(name); If it is the get method, directly xmlHttp.send(null);

(4). Server-side request parameters distinguish between Get and Post . If it is the get method, then $username = $_GET["username"]; If it is the post method, then $username = $_POST["username"];

In short, the GET method transmits a small amount of data and has high processing efficiency. The security is low and will be cached, while the opposite is true for POST.

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

PHP and Python: Different Paradigms ExplainedApr 18, 2025 am 12:26 AM

PHP is mainly procedural programming, but also supports object-oriented programming (OOP); Python supports a variety of paradigms, including OOP, functional and procedural programming. PHP is suitable for web development, and Python is suitable for a variety of applications such as data analysis and machine learning.

PHP and Python: A Deep Dive into Their HistoryApr 18, 2025 am 12:25 AM

PHP originated in 1994 and was developed by RasmusLerdorf. It was originally used to track website visitors and gradually evolved into a server-side scripting language and was widely used in web development. Python was developed by Guidovan Rossum in the late 1980s and was first released in 1991. It emphasizes code readability and simplicity, and is suitable for scientific computing, data analysis and other fields.

Choosing Between PHP and Python: A GuideApr 18, 2025 am 12:24 AM

PHP is suitable for web development and rapid prototyping, and Python is suitable for data science and machine learning. 1.PHP is used for dynamic web development, with simple syntax and suitable for rapid development. 2. Python has concise syntax, is suitable for multiple fields, and has a strong library ecosystem.

PHP and Frameworks: Modernizing the LanguageApr 18, 2025 am 12:14 AM

PHP remains important in the modernization process because it supports a large number of websites and applications and adapts to development needs through frameworks. 1.PHP7 improves performance and introduces new features. 2. Modern frameworks such as Laravel, Symfony and CodeIgniter simplify development and improve code quality. 3. Performance optimization and best practices further improve application efficiency.

PHP's Impact: Web Development and BeyondApr 18, 2025 am 12:10 AM

PHPhassignificantlyimpactedwebdevelopmentandextendsbeyondit.1)ItpowersmajorplatformslikeWordPressandexcelsindatabaseinteractions.2)PHP'sadaptabilityallowsittoscaleforlargeapplicationsusingframeworkslikeLaravel.3)Beyondweb,PHPisusedincommand-linescrip

How does PHP type hinting work, including scalar types, return types, union types, and nullable types?Apr 17, 2025 am 12:25 AM

PHP type prompts to improve code quality and readability. 1) Scalar type tips: Since PHP7.0, basic data types are allowed to be specified in function parameters, such as int, float, etc. 2) Return type prompt: Ensure the consistency of the function return value type. 3) Union type prompt: Since PHP8.0, multiple types are allowed to be specified in function parameters or return values. 4) Nullable type prompt: Allows to include null values and handle functions that may return null values.

How does PHP handle object cloning (clone keyword) and the __clone magic method?Apr 17, 2025 am 12:24 AM

In PHP, use the clone keyword to create a copy of the object and customize the cloning behavior through the \_\_clone magic method. 1. Use the clone keyword to make a shallow copy, cloning the object's properties but not the object's properties. 2. The \_\_clone method can deeply copy nested objects to avoid shallow copying problems. 3. Pay attention to avoid circular references and performance problems in cloning, and optimize cloning operations to improve efficiency.

PHP vs. Python: Use Cases and ApplicationsApr 17, 2025 am 12:23 AM

PHP is suitable for web development and content management systems, and Python is suitable for data science, machine learning and automation scripts. 1.PHP performs well in building fast and scalable websites and applications and is commonly used in CMS such as WordPress. 2. Python has performed outstandingly in the fields of data science and machine learning, with rich libraries such as NumPy and TensorFlow.

See all articles

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

R.E.P.O. Energy Crystals Explained and What They Do (Yellow Crystal)

1 months agoBy尊渡假赌尊渡假赌尊渡假赌

R.E.P.O. Best Graphic Settings

1 months agoBy尊渡假赌尊渡假赌尊渡假赌

Assassin's Creed Shadows: Seashell Riddle Solution

3 weeks agoByDDD

What's New in Windows 11 KB5054979 & How to Fix Update Issues

2 weeks agoByDDD

Will R.E.P.O. Have Crossplay?

1 months agoBy尊渡假赌尊渡假赌尊渡假赌

Hot Tools

DVWA

Damn Vulnerable Web App (DVWA) is a PHP/MySQL web application that is very vulnerable. Its main goals are to be an aid for security professionals to test their skills and tools in a legal environment, to help web developers better understand the process of securing web applications, and to help teachers/students teach/learn in a classroom environment Web application security. The goal of DVWA is to practice some of the most common web vulnerabilities through a simple and straightforward interface, with varying degrees of difficulty. Please note that this software

PhpStorm Mac version

The latest (2018.2.1) professional PHP integrated development tool

SublimeText3 English version

Recommended: Win version, supports code prompts!

SecLists

SecLists is the ultimate security tester's companion. It is a collection of various types of lists that are frequently used during security assessments, all in one place. SecLists helps make security testing more efficient and productive by conveniently providing all the lists a security tester might need. List types include usernames, passwords, URLs, fuzzing payloads, sensitive data patterns, web shells, and more. The tester can simply pull this repository onto a new test machine and he will have access to every type of list he needs.

ZendStudio 13.5.1 Mac

Powerful PHP integrated development environment

Hot Topics

Where is the login entrance for gmail email?

7561

CakePHP Tutorial

1384

What is the format of the account name of steam

win11 activation key permanent

nyt connections hints and answers