Home  >  Article  >  Backend Development  >  How to get a single value from an array in php

How to get a single value from an array in php

小云云
小云云Original
2018-03-14 09:32:424510browse

How to extract a single value from an array in php. Below, I will share with you a method for extracting a single value from an array in php. It has a good reference value and I hope it can help you.

1. Array arr

var_dump(arr) has the following values:


array (size=3)
 'delete' => 
 array (size=3)
  0 => string 'HBSFlyRecode20170222-101501.txt' (length=31)
  1 => string 'HBSFlyRecode20170222-105502.txt' (length=31)
  2 => string 'HBSFlyRecode20170222-108803.txt' (length=31)
 'new' => 
 array (size=3)
  0 => string 'HBSFlyRecode20170223-101504.txt' (length=31)
  1 => string 'HBSFlyRecode20170223-105505.txt' (length=31)
  2 => string 'HBSFlyRecode20170223-108806.txt' (length=31)
 'old' => 
 array (size=3)
  0 => string 'HBSFlyRecode20170221-101507.txt' (length=31)
  1 => string 'HBSFlyRecode20170221-105508.txt' (length=31)
  2 => string 'HBSFlyRecode20170221-108809.txt' (length=31)


echo $arr['old'][0];
打印出: HBSFlyRecode20170221-101507.txt

But if arr is in object form, the print result is as follows:


var_dump(arr)
object(stdClass)[1]
 public 'delete' => 
 array (size=3)
  0 => string 'HBSFlyRecode20170222-101501.txt' (length=31)
  1 => string 'HBSFlyRecode20170222-105502.txt' (length=31)
  2 => string 'HBSFlyRecode20170222-108803.txt' (length=31)
 public 'new' => 
 array (size=3)
  0 => string 'HBSFlyRecode20170223-101504.txt' (length=31)
  1 => string 'HBSFlyRecode20170223-105505.txt' (length=31)
  2 => string 'HBSFlyRecode20170223-108806.txt' (length=31)
 public 'old' => 
 array (size=3)
  0 => string 'HBSFlyRecode20170221-101507.txt' (length=31)
  1 => string 'HBSFlyRecode20170221-105508.txt' (length=31)
  2 => string 'HBSFlyRecode20170221-108809.txt' (length=31)

You cannot use $arr['old'][0] to get the value, you can use the arr object The value of the foreach method that is common to arrays:


function getValue($arr){
 foreach($arr as $key => $value){
  if(is_array($value)){
   getValue($value);
  }else{
   echo $value."<br>";
  }
 }
}

If arr is in object form, you can convert the object into array form. Here is an example A shortcut:

1. $object_json = json_encode($arr); what you get is the object

$json = json_encode($arr,true); what you get It is pure json

2. What json_decode($object_json) and json_decode($json) get is an array object

json_decode($object_json,true) and json_decode($json,true) It’s an array

To sum up, you can convert an array object into an array:


arr=jsondecode(jsonencode(arr=jsondecode(jsonencode(arr,true),true);

project I found this problem in . It is recommended that when converting json and array in php, you should add true to the second parameter of json_encode() and json_decode(), that is:


##

json_encode(arr,true);jsondecode(arr,true);jsondecode(json,true);

The above is the detailed content of How to get a single value from an array in php. For more information, please follow other related articles on the PHP Chinese website!

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