用 php 编码 json 并解析

Question

我需要为运行一个具有这种结构的js创建两个变量

var sets = [{"label":"PHP","size":"6"},{"label":"SQL","size":"1"}];

var overlaps = [ {"sets":[0,1],"size":"0"}];

我正在尝试用 php 动态地创建它，就像这样

$sets[] = array("label" =>"PHP", "size" => "6");
$overlaps[] = array("sets" => array(0,1), "size" => "0");
print json_encode(array($sets, $overlaps));

在ajax我这样做

$.post(action
        , {param:param}
        , function(returned_data){

            console.log(returned_data);
            var json = $.parseJSON(returned_data);
            sets = json[0];
            overlaps = json[1];
});

Console.log 转储这个

[[{"label":"PHP","size":"6"},{"label":"SQL","size":"1"},{"label":"JQuery","size":"1"}],[{"sets":[0,2],"size":"1"}]]

错误是“无法读取未定义的属性'push'”

怎么了？如何解析 json 并将每个部分分配给变量？

Answer 1

我认为您不需要将其解析为 JSON，控制台暗示它已经是 object。此外，return 几乎在所有语言中都是保留字（语言结构），因此您应该养成不将其用于变量名的习惯。

$.post(action
    , {param:param}
    , function(return_data){
        return_data = typeof return_data=='object' ? return_data : $.parseJSON(return_data);
        //The line above parses the string only if the browser didn't already recognize it as a JSON-object.

        console.log(return_data);
        sets = return_data[0];
        overlaps = return_data[1];
   });

此外，您应该在 PHP 中设置 header（那时肯定不需要 $.parseJSON）：

$sets[] = array("label" =>"PHP", "size" => "6");
$overlaps[] = array("sets" => array(0,1), "size" => "0");
header('Content-type: application/json'); //I added this line
echo json_encode(array($sets, $overlaps));

Answer 2

奇怪的错误。可能是因为您使用保留字作为变量。

Answer 3

jQuery $.post 已经期望 JSON 所以不需要 JSON 解析 .

$.post(action
    , {param:param}
    , function(returned_data){

        console.log(returned_data);
        var json = returned_data;
        sets = json[0];
        overlaps = json[1];
});

用 php 编码 json 并解析

Enconding json with php and parsing

php

parsing

json