Detailed explanation of the use of $.ajax()
This time I will bring you a detailed explanation of the use of $.ajax(), what are the precautions when using $.ajax(), the following is a practical case, let's take a look.
AJAX is a technology that exchanges data with the server and can update part of a web page while supplementing the entire page. Next, this article will introduce you to some common methods of ajax. If necessary, you can learn together.
1.url:
is required to be a String type parameter, (default is the current page address) to which the request is sent.
2.type:
requires parameters of String type, and the request method (post or get) defaults to get. Note that other http request methods, such as put and delete, can also be used, but are only supported by some browsers.
3.timeout:
Requires a parameter of type Number and sets the request timeout (milliseconds). This setting will override the global setting of the $.ajaxSetup() method.
4.async:
Requires Boolean type parameters. The default setting is true. All requests are asynchronous requests. If you need to send synchronous requests, set this option to false. Note that a synchronous request will lock the browser, and the user must wait for the request to complete before other operations can be performed.
5.cache:
Requires Boolean type parameters, the default is true (when dataType is script, the default is false), Setting to false will not load request information from the browser cache.
6.data:
Requires parameters of type Object or String, data sent to the server. If it is not a string, it will be automatically converted to string format. The get request will be appended to the url. To prevent this automatic conversion, check the processData option. The object must be in key/value format, for example {foo1:"bar1",foo2:"bar2"} is converted to &foo1=bar1&foo2=bar2. If it is an array, JQuery will automatically assign the same name to different values. For example, {foo:["bar1","bar2"]} is converted to &foo=bar1&foo=bar2.
7.dataType:
Requires parameters of String type, expected data type returned by the server. If not specified, JQuery will automatically return responseXML or responseText based on the http package mime information and pass it as the callback function parameter. The available types are as follows:
xml: Returns an XML document that can be processed with JQuery.
html: Returns plain text HTML information; the included script tag will be executed when inserted into the DOM.
script: Returns plain text JavaScript code. Results are not automatically cached. Unless cache parameters are set. Note that when making remote requests (not under the same domain), all post requests will be converted into get requests.
json: Return JSON data.
jsonp: JSONP format. When calling a function using the SONP form, such as myurl?callback=?, JQuery will automatically replace the last "?" with the correct function name to execute the callback function.
text: Returns a plain text string.
8.beforeSend:
requires parameters of Function type. You can modify the function of the XMLHttpRequest object before sending the request, such as adding a custom HTTP head. If false is returned in beforeSend, this ajax request can be canceled. The XMLHttpRequest object is the only parameter.
function(XMLHttpRequest){
this; //调用本次ajax请求时传递的options参数
}9.complete:
requires a parameter of Function type, a callback function called after the request is completed (both when the request succeeds or fails) transfer). Parameters: XMLHttpRequest object and a string describing the successful request type.
function(XMLHttpRequest, textStatus){
this; //调用本次ajax请求时传递的options参数
}10.success:
requires a parameter of Function type. The callback function called after the request is successful has two parameters.
(1) Data returned by the server and processed according to the dataType parameter.
(2)描述状态的字符串。
function(data, textStatus){
//data可能是xmlDoc、jsonObj、html、text等等
this; //调用本次ajax请求时传递的options参数
}11.error:
要求为Function类型的参数，请求失败时被调用的函数。该函数有3个参数，即XMLHttpRequest对象、错误信息、捕获的错误对象(可选)。ajax事件函数如下：
function(XMLHttpRequest, textStatus, errorThrown){
//通常情况下textStatus和errorThrown只有其中一个包含信息
this; //调用本次ajax请求时传递的options参数
}12.contentType：
要求为String类型的参数，当发送信息至服务器时，内容编码类型默认为"application/x-www-form-urlencoded"。该默认值适合大多数应用场合。
13.dataFilter：
要求为Function类型的参数，给Ajax返回的原始数据进行预处理的函数。提供data和type两个参数。data是Ajax返回的原始数据，type是调用jQuery.ajax时提供的dataType参数。函数返回的值将由jQuery进一步处理。
function(data, type){
//返回处理后的数据
return data;
}14.dataFilter：
要求为Function类型的参数，给Ajax返回的原始数据进行预处理的函数。提供data和type两个参数。data是Ajax返回的原始数据，type是调用jQuery.ajax时提供的dataType参数。函数返回的值将由jQuery进一步处理。
function(data, type){
//返回处理后的数据
return data;
}15.global：
要求为Boolean类型的参数，默认为true。表示是否触发全局ajax事件。设置为false将不会触发全局ajax事件，ajaxStart或ajaxStop可用于控制各种ajax事件。
16.ifModified：
要求为Boolean类型的参数，默认为false。仅在服务器数据改变时获取新数据。服务器数据改变判断的依据是Last-Modified头信息。默认值是false，即忽略头信息。
17.jsonp：
要求为String类型的参数，在一个jsonp请求中重写回调函数的名字。该值用来替代在"callback=?"这种GET或POST请求中URL参数里的"callback"部分，例如{jsonp:'onJsonPLoad'}会导致将"onJsonPLoad=?"传给服务器。
18.username：
要求为String类型的参数，用于响应HTTP访问认证请求的用户名。
19.password：
要求为String类型的参数，用于响应HTTP访问认证请求的密码。
20.processData：
要求为Boolean类型的参数，默认为true。默认情况下，发送的数据将被转换为对象（从技术角度来讲并非字符串）以配合默认内容类型"application/x-www-form-urlencoded"。如果要发送DOM树信息或者其他不希望转换的信息，请设置为false。
21.scriptCharset：
要求为String类型的参数，只有当请求时dataType为"jsonp"或者"script"，并且type是GET时才会用于强制修改字符集(charset)。通常在本地和远程的内容编码不同时使用。
案例代码：
$(function(){
$('#send').click(function(){
$.ajax({
type: "GET",
url: "test.json",
data: {username:$("#username").val(), content:$("#content").val()},
dataType: "json",
success: function(data){
$('#resText').empty(); //清空resText里面的所有内容
var html = '';
$.each(data, function(commentIndex, comment){
html += '<p class="comment"><h6>' + comment['username']
+ ':</h6><p class="para"' + comment['content']
+ '</p></p>';
});
$('#resText').html(html);
}
});
});
});相信看了本文案例你已经掌握了方法，更多精彩请关注php中文网其它相关文章！
推荐阅读：
The above is the detailed content of Detailed explanation of the use of $.ajax(). For more information, please follow other related articles on the PHP Chinese website!
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
Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!
Hot Article
Hot Tools
Notepad++7.3.1
Easy-to-use and free code editor
SublimeText3 Chinese version
Chinese version, very easy to use
Zend Studio 13.0.1
Powerful PHP integrated development environment
Dreamweaver CS6
Visual web development tools
SublimeText3 Mac version
God-level code editing software (SublimeText3)
Hot Topics
What software is crystaldiskmark? -How to use crystaldiskmark?
Mar 18, 2024 pm 02:58 PM
CrystalDiskMark is a small HDD benchmark tool for hard drives that quickly measures sequential and random read/write speeds. Next, let the editor introduce CrystalDiskMark to you and how to use crystaldiskmark~ 1. Introduction to CrystalDiskMark CrystalDiskMark is a widely used disk performance testing tool used to evaluate the read and write speed and performance of mechanical hard drives and solid-state drives (SSD). Random I/O performance. It is a free Windows application and provides a user-friendly interface and various test modes to evaluate different aspects of hard drive performance and is widely used in hardware reviews
How to download foobar2000? -How to use foobar2000
Mar 18, 2024 am 10:58 AM
foobar2000 is a software that can listen to music resources at any time. It brings you all kinds of music with lossless sound quality. The enhanced version of the music player allows you to get a more comprehensive and comfortable music experience. Its design concept is to play the advanced audio on the computer The device is transplanted to mobile phones to provide a more convenient and efficient music playback experience. The interface design is simple, clear and easy to use. It adopts a minimalist design style without too many decorations and cumbersome operations to get started quickly. It also supports a variety of skins and Theme, personalize settings according to your own preferences, and create an exclusive music player that supports the playback of multiple audio formats. It also supports the audio gain function to adjust the volume according to your own hearing conditions to avoid hearing damage caused by excessive volume. Next, let me help you
How to use Baidu Netdisk app
Mar 27, 2024 pm 06:46 PM
Cloud storage has become an indispensable part of our daily life and work nowadays. As one of the leading cloud storage services in China, Baidu Netdisk has won the favor of a large number of users with its powerful storage functions, efficient transmission speed and convenient operation experience. And whether you want to back up important files, share information, watch videos online, or listen to music, Baidu Cloud Disk can meet your needs. However, many users may not understand the specific use method of Baidu Netdisk app, so this tutorial will introduce in detail how to use Baidu Netdisk app. Users who are still confused can follow this article to learn more. ! How to use Baidu Cloud Network Disk: 1. Installation First, when downloading and installing Baidu Cloud software, please select the custom installation option.
How to use NetEase Mailbox Master
Mar 27, 2024 pm 05:32 PM
NetEase Mailbox, as an email address widely used by Chinese netizens, has always won the trust of users with its stable and efficient services. NetEase Mailbox Master is an email software specially created for mobile phone users. It greatly simplifies the process of sending and receiving emails and makes our email processing more convenient. So how to use NetEase Mailbox Master, and what specific functions it has. Below, the editor of this site will give you a detailed introduction, hoping to help you! First, you can search and download the NetEase Mailbox Master app in the mobile app store. Search for "NetEase Mailbox Master" in App Store or Baidu Mobile Assistant, and then follow the prompts to install it. After the download and installation is completed, we open the NetEase email account and log in. The login interface is as shown below
BTCC tutorial: How to bind and use MetaMask wallet on BTCC exchange?
Apr 26, 2024 am 09:40 AM
MetaMask (also called Little Fox Wallet in Chinese) is a free and well-received encryption wallet software. Currently, BTCC supports binding to the MetaMask wallet. After binding, you can use the MetaMask wallet to quickly log in, store value, buy coins, etc., and you can also get 20 USDT trial bonus for the first time binding. In the BTCCMetaMask wallet tutorial, we will introduce in detail how to register and use MetaMask, and how to bind and use the Little Fox wallet in BTCC. What is MetaMask wallet? With over 30 million users, MetaMask Little Fox Wallet is one of the most popular cryptocurrency wallets today. It is free to use and can be installed on the network as an extension
Detailed explanation of obtaining administrator rights in Win11
Mar 08, 2024 pm 03:06 PM
Windows operating system is one of the most popular operating systems in the world, and its new version Win11 has attracted much attention. In the Win11 system, obtaining administrator rights is an important operation. Administrator rights allow users to perform more operations and settings on the system. This article will introduce in detail how to obtain administrator permissions in Win11 system and how to effectively manage permissions. In the Win11 system, administrator rights are divided into two types: local administrator and domain administrator. A local administrator has full administrative rights to the local computer
Detailed explanation of division operation in Oracle SQL
Mar 10, 2024 am 09:51 AM
Detailed explanation of division operation in OracleSQL In OracleSQL, division operation is a common and important mathematical operation, used to calculate the result of dividing two numbers. Division is often used in database queries, so understanding the division operation and its usage in OracleSQL is one of the essential skills for database developers. This article will discuss the relevant knowledge of division operations in OracleSQL in detail and provide specific code examples for readers' reference. 1. Division operation in OracleSQL
Teach you how to use the new advanced features of iOS 17.4 'Stolen Device Protection'
Mar 10, 2024 pm 04:34 PM
Apple rolled out the iOS 17.4 update on Tuesday, bringing a slew of new features and fixes to iPhones. The update includes new emojis, and EU users will also be able to download them from other app stores. In addition, the update also strengthens the control of iPhone security and introduces more "Stolen Device Protection" setting options to provide users with more choices and protection. "iOS17.3 introduces the "Stolen Device Protection" function for the first time, adding extra security to users' sensitive information. When the user is away from home and other familiar places, this function requires the user to enter biometric information for the first time, and after one hour You must enter information again to access and change certain data, such as changing your Apple ID password or turning off stolen device protection.
