In PHP, you can use the json_encode() function to convert array data into json. The json_encode() function can json encode variables. If the conversion is successful, it will return json data, otherwise it will return false.
The operating environment of this tutorial: windows7 system, PHP7.1 version, DELL G3 computer
Now when we need to useajax
How to convert php arrays to json when interacting with the background.
The powerful PHP has provided built-in functions: json_encode()
and json_decode()
. It is easy to understand that json_encode() converts a PHP array into Json. On the contrary, json_decode()
is to convert Json into a PHP array.
The specific form of Json is:
1. Object
The object is an unordered "'name/value' pair" gather. An object starts with "{" (left bracket) and ends with "}" (right bracket). Each "name" is followed by a ":" (colon); "name/value" pairs are separated by a "," (comma).
2. Array
An array is an ordered collection of values (value
). An array starts with "[" (left bracket) and ends with "]" (right bracket). Values are separated by "," (comma).
Note: The two forms of objects and arrays are called differently in JS. Objects are called with "." and arrays are called with subscripts [0] and [1]. Also note that when passing a Json string, values of type string
must be enclosed in quotes.
Instance 1:
$array = array("name" => "Eric","age" => 23); echo json_encode($array);
The program will print out:
{“name”:”Eric”,”age”:23}
Instance 2:
$array = array(0 => "Eric", 1 => 23); echo json_encode($array);
The program will output:
["Eric",23]
It can be seen from the above two examples that the two calls in js are different. The keys of the PHP array are all numbers, then json_encode() returns Json in the form of an array, if the keys of the PHP array are all strings. Then json_encode() will return Json in the form of an object.
In fact, as long as there is a key in the form of a string in the key of the PHP array, then json_encode() will return Json in the form of an object. This is not correct. Because, although no errors will occur in the PHP code, if such a Json is passed to a JS function, JS will treat the Json as an object, and it is impossible for an object to use numbers as attribute names. In other words, JS does not know what this is: user.0.username (the middle is the number zero)
Recommended learning: php video tutorial
The above is the detailed content of How to convert PHP array data to json. For more information, please follow other related articles on the PHP Chinese website!

php把负数转为正整数的方法:1、使用abs()函数将负数转为正数,使用intval()函数对正数取整,转为正整数,语法“intval(abs($number))”;2、利用“~”位运算符将负数取反加一,语法“~$number + 1”。

实现方法:1、使用“sleep(延迟秒数)”语句,可延迟执行函数若干秒;2、使用“time_nanosleep(延迟秒数,延迟纳秒数)”语句,可延迟执行函数若干秒和纳秒;3、使用“time_sleep_until(time()+7)”语句。

php除以100保留两位小数的方法:1、利用“/”运算符进行除法运算,语法“数值 / 100”;2、使用“number_format(除法结果, 2)”或“sprintf("%.2f",除法结果)”语句进行四舍五入的处理值,并保留两位小数。

判断方法:1、使用“strtotime("年-月-日")”语句将给定的年月日转换为时间戳格式;2、用“date("z",时间戳)+1”语句计算指定时间戳是一年的第几天。date()返回的天数是从0开始计算的,因此真实天数需要在此基础上加1。

php字符串有下标。在PHP中,下标不仅可以应用于数组和对象,还可应用于字符串,利用字符串的下标和中括号“[]”可以访问指定索引位置的字符,并对该字符进行读写,语法“字符串名[下标值]”;字符串的下标值(索引值)只能是整数类型,起始值为0。

方法:1、用“str_replace(" ","其他字符",$str)”语句,可将nbsp符替换为其他字符;2、用“preg_replace("/(\s|\ \;||\xc2\xa0)/","其他字符",$str)”语句。

php判断有没有小数点的方法:1、使用“strpos(数字字符串,'.')”语法,如果返回小数点在字符串中第一次出现的位置,则有小数点;2、使用“strrpos(数字字符串,'.')”语句,如果返回小数点在字符串中最后一次出现的位置,则有。

在php中,可以使用substr()函数来读取字符串后几个字符,只需要将该函数的第二个参数设置为负值,第三个参数省略即可;语法为“substr(字符串,-n)”,表示读取从字符串结尾处向前数第n个字符开始,直到字符串结尾的全部字符。


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

SAP NetWeaver Server Adapter for Eclipse
Integrate Eclipse with SAP NetWeaver application server.

Dreamweaver Mac version
Visual web development tools

ZendStudio 13.5.1 Mac
Powerful PHP integrated development environment

Atom editor mac version download
The most popular open source editor

SublimeText3 Linux new version
SublimeText3 Linux latest version
