PHP中生成json信息的方法

大家好，又见面了，我是全栈君。

 1 <?php
 2 
 3 //php中生成json信息
 4 //json_encode(数组/对象)
 5 
 6 $color = array('red','blue','green'); //【索引数组】
 7 echo json_encode($color),"<br />"; //["red","blue","green"]
 8 
 9 $animal = array('east'=>'tiger','north'=>'wolf','south'=>'monkey'); //【关联数组】
10 echo json_encode($animal),"<br />";//{"east":"tiger","north":"wolf","south":"monkey"}
11 
12 //【索引关联数组】
13 $animal2 = array('east'=>'tiger','north'=>'wolf','duck','south'=>'monkey');
14 echo json_encode($animal2),"<br />";//{"east":"tiger","north":"wolf","0":"duck","south":"monkey"}
15 
16 //[{},{},{}]
17 //{"weatherinfo":{"city":"北京","cityid":"101010100","temp":"9","WD":"南风","WS":"2级","SD":"26%","WSE":"2","time":"10:20","isRadar":"1","Radar":"JC_RADAR_AZ9010_JB","njd":"暂无实况","qy":"1014"}}
18 //{名称:[],名称:[],名称:[]}
19 
20 
21 //【对象生成json信息】
22 class Person{
23     public $addr = "beijing";
24     public $height = 170;
25     public function study(){
26         echo "study php";
27     }
28 }
29 $tom = new Person();
30 //只是对象的属性给生成json信息
31 echo json_encode($tom);//{"addr":"beijing","height":170}

1.json

json_encode(数组/对象)————>生成json信息，

json_decode(json信息); 反编码json信息

对json字符串信息进行反编码，变为当前语言可以识别的信息。

2. javascript接收处理json信息

通过eval()把接收的json字符串变成真实的对象信息

代码如下：

 1 <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">  2 <html>  3 <head>  4 <title>新建网页</title>  5 <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />  6 <meta name="description" content="" />  7 <meta name="keywords" content="" />  8  9 <script type="text/javascript"> 10 function showweather(){ 11 //利用ajax获得天气预报信息 12 //利用javascript+dom处理并显示天气信息 13 var xhr = new XMLHttpRequest(); 14  xhr.onreadystatechange = function(){ 15 if(xhr.readyState==4){ 16 //alert(xhr.responseText); 17  console.log(typeof xhr.responseText);//string 18 //要把接收的“字符串”变为“对象” 19 //'{"addr":"\u5317\u4eac","temp":"9-22","wind":"north4-5"}' 20  eval("var info="+xhr.responseText); 21 22 var str = "地址："+info.addr+";温度:"+info.temp+";风向:"+info.wind; 23  document.getElementById('result').innerHTML = str; 24  } 25  } 26  xhr.open('get','./03.php'); 27  xhr.send(null); 28  } 29  window.onload = function(){ 30  showweather(); 31  } 32 33 // //s字符串变为对象obj 34 // var s = "{name:'tom',height:170}"; 35 // //"var obj="+"{name:'tom',height:170}"====>"var obj={name:'tom',height:170}" 36 // //console.log("var obj="+s);  37 // eval("var obj="+s); 38 // console.log(obj);//Object { name="tom", height=170} 39 40 </script> 41 42 <style type="text/css"> 43 </style> 44 </head> 45 <body> 46 <h2>获得天气预报接口信息</h2> 47 <div id="result"></div> 48 </body> 49 </html>