Perfect processing of json data cannot perform success
This time I will bring you the problems of perfect processing of json data that cannot execute success, and perfect json data that cannot execute success. What are the precautions?The following is a practical case, let's take a look.
1.jquery obtains json data through the ajax method and does not execute the success callback method
Problem description: jquery obtains json data through the ajax method and does not execute the success callback method
Cause of the problem: There is a problem with the json format or it does not conform to the standard writing method, resulting in the error callback method being always executed.
Solution: Make the json format must comply with the following three standard writing methods:
1 ) Key name: enclosed in double quotes;
2) String : enclosed in double quotes;
3) Numbers and Boolean values do not need to use double quotes Brackets;
Note: Must be double brackets!
2. Ajax uses json in jQueryData typeAlways skip the success execution error statement
Execute the function
error : function(XMLHttpRequest, textStatus, errorThrown) { //这个error函数调试时非常有用,如果解析不正确,将会弹出错误框 alert(XMLHttpRequest.responseText); alert(XMLHttpRequest.status); alert(XMLHttpRequest.readyState); alert(textStatus); // parser error; }
and you will understand the error message; the
pop-up box displays:
<!DOCTYPE html PUBLIC "-//W3C //DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD /xhtml1-transitional.dtd">以 及<?xml version="1.0" encoding="gb2312" ?>
These two sentences, although I don’t know why, After I deleted it, success was successfully executed
3. When the URL in $.ajax() crosses domains, success is always not executed and an error is always entered
1) I added ServletActionContext.getResponse().setHeader("Access-Control-Allow-Origin", "*");
to solve cross-domain issues Question, you can successfully enter success
2) dataType: "json",
Remove it and see if you can enter success.
dataType is the type of information expected to be returned by the server.
Reason: The returned data type must conform to the defined data type. That is, if the dataType you define is of json type, then the returned data must be json, otherwise the program block in error will be executed.
(1) At the same time, special attention needs to be paid to whether the returned JSON data is in strict JSON format.
(2) You should also be seriously concerned when the background returns a List data (the items in the List When the data is in JSON format), if there is dirty data, it is not in strict JSON format.
I believe you have mastered the method after reading the case in this article. For more exciting information, please pay attention to other related articles on the php Chinese website!
Recommended reading:
What data types can ajax handle returned by the server?
Display progress during Ajax request
The above is the detailed content of Perfect processing of json data cannot perform success. 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

1. First, we right-click the blank space of the taskbar and select the [Task Manager] option, or right-click the start logo, and then select the [Task Manager] option. 2. In the opened Task Manager interface, we click the [Services] tab on the far right. 3. In the opened [Service] tab, click the [Open Service] option below. 4. In the [Services] window that opens, right-click the [InternetConnectionSharing(ICS)] service, and then select the [Properties] option. 5. In the properties window that opens, change [Open with] to [Disabled], click [Apply] and then click [OK]. 6. Click the start logo, then click the shutdown button, select [Restart], and complete the computer restart.

In the process of PHP development, dealing with special characters is a common problem, especially in string processing, special characters are often escaped. Among them, converting special characters into single quotes is a relatively common requirement, because in PHP, single quotes are a common way to wrap strings. In this article, we will explain how to handle special character conversion single quotes in PHP and provide specific code examples. In PHP, special characters include but are not limited to single quotes ('), double quotes ("), backslash (), etc. In strings

Performance optimization methods for converting PHP arrays to JSON include: using JSON extensions and the json_encode() function; adding the JSON_UNESCAPED_UNICODE option to avoid character escaping; using buffers to improve loop encoding performance; caching JSON encoding results; and considering using a third-party JSON encoding library.

Annotations in the Jackson library control JSON serialization and deserialization: Serialization: @JsonIgnore: Ignore the property @JsonProperty: Specify the name @JsonGetter: Use the get method @JsonSetter: Use the set method Deserialization: @JsonIgnoreProperties: Ignore the property @ JsonProperty: Specify name @JsonCreator: Use constructor @JsonDeserialize: Custom logic

In-depth understanding of PHP: Implementation method of converting JSONUnicode to Chinese During development, we often encounter situations where we need to process JSON data, and Unicode encoding in JSON will cause us some problems in some scenarios, especially when Unicode needs to be converted When encoding is converted to Chinese characters. In PHP, there are some methods that can help us achieve this conversion process. A common method will be introduced below and specific code examples will be provided. First, let us first understand the Un in JSON

PHP arrays can be converted to JSON strings through the json_encode() function (for example: $json=json_encode($array);), and conversely, the json_decode() function can be used to convert from JSON to arrays ($array=json_decode($json);) . Other tips include avoiding deep conversions, specifying custom options, and using third-party libraries.

PHP provides the following functions to process JSON data: Parse JSON data: Use json_decode() to convert a JSON string into a PHP array. Create JSON data: Use json_encode() to convert a PHP array or object into a JSON string. Get specific values of JSON data: Use PHP array functions to access specific values, such as key-value pairs or array elements.

JSON (JavaScriptObjectNotation) is a lightweight data exchange format commonly used for data exchange between web applications. When processing JSON data, we often encounter Unicode-encoded Chinese characters (such as "u4e2du6587") and need to convert them into readable Chinese characters. In PHP, we can achieve this conversion through some simple methods. Next, we will detail how to convert JSONUnico
