PHP 计数 JSON 数组
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PHP count JSON array
提问by Buneme Kyakilika
I have searched SO but couldn't find an answer.My PHP script is receiving some JSON by http post that looks like this:
我已经搜索过，但找不到答案。我的 PHP 脚本正在通过 http 帖子接收一些 JSON，如下所示：
{
"task": [
{
"task_id": "3",
"task_due": "Oct 26 11:25",
"task_completed": "FALSE",
"task_desc": "fff",
"task_time": "20131026_112531",
"task_name": "fff"
},
{
"task_id": "2",
"task_due": "Oct 26 11:25",
"task_completed": "FALSE",
"task_desc": "rff",
"task_time": "20131026_112522",
"task_name": "xff"
},
{
"task_id": "1",
"task_due": "Oct 26 11:25",
"task_completed": "FALSE",
"task_desc": "fggg",
"task_time": "20131026_112516",
"task_name": "ff"
}
]}
As you can see, there are 3 items, but when I turn it into a PHP array object and count the items, I'm returned 1, when it should be 3, here is my PHP code:
正如你所看到的，有 3 个项目，但是当我把它变成一个 PHP 数组对象并计算这些项目时，我返回了 1，当它应该是 3 时，这是我的 PHP 代码：
$json_tasks = $_POST["json_array"];
$task_array = json_decode($json_tasks,true);
echo count($task_array);
And echo countprints out '1' not '3'.
并echo count打印出“1”而不是“3”。
回答by Oswald
Try echo count($task_array['task']);
尝试 echo count($task_array['task']);
In general, if you wonder what the structure of the value of a variable $varis, do a
通常，如果您想知道变量值的结构是什么$var，请执行以下操作
<pre><?php var_export($var, true); ?></pre>
Advantage of this function over alternatives such as serializeand print_ris, that it prints PHP code (and is thus readable by anyone who understands PHP (which is likely if you program in PHP)). Disadvantage of var_exportis, that it cannot handle circular structures (e.g. if $a->b == $a), but neither can JSON.
在替代品，如这个功能的优势serialize，并print_r是，它打印的PHP代码（并因此被人谁了解PHP（这很可能是，如果你在PHP程序）可读）。缺点var_export是，它不能处理循环结构（例如 if $a->b == $a），但 JSON 也不能。
回答by coltphp
$task_array = json_decode($json_tasks);
count($task_array->task);
EX: 3
例如：3
From Taiwan
来自台湾
回答by Deepanshu Goyal
Well the 3items are in 1item "task"so, you have one array named task and the 3 elements are in it
那么3项目在1项目中，"task"所以你有一个名为 task 的数组，其中有 3 个元素
try
尝试
echo count($task_array['task']);
EDIT :
编辑 ：
please use the below code to print the array in correct pattern
请使用以下代码以正确的模式打印数组
echo '<pre>';
print_r($task_array['task']);
exit();
回答by Karthick
try this code, here i can able to count the number of objects with specific value
试试这个代码，在这里我可以计算具有特定值的对象的数量
here's my data.json file content
这是我的 data.json 文件内容
{"likes":[
{"user_id":1,"time":"12:04pm"},
{"user_id":2,"time":"02:04pm"},
{"user_id":67,"time":"11:04pm"},
{"user_id":1,"time":"12:04pm"}
]}
here's the php code
这是php代码
<?php
$jsonData = file_get_contents("data.json");
$data = json_decode($jsonData,true);
$total = 0;
foreach ($data["likes"] as $value) {
if($value["user_id"]==1){
$total = $total+1;
}
}
echo $total;
?>
output will be
输出将是
2
