jquery's $getjson call and get the remote JSON string problem_javascript skills

The code is as follows:

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click

where ajax6.asp is

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response.Write("{name:'peter',age:18}");
%>

Why can’t I get it? , I want to get the json of asp.
The key problem solved is: key and value require double quotes, as follows:

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response.Write("{""name"":""peter"",""age"":""18″"}")

Commonly used in jQuery GetJSON is called to obtain the remote JSON string, convert it into a JSON object, and if successful, execute the callback function. The prototype is as follows:
jQuery.getJSON( url, [data], [callback] ) loads JSON data across domains.
url: the address to send the request
data: (optional) key/value parameters to be sent
callback: (optional) callback function when loading is successful
is mainly used for the client to obtain the server JSON data. Simple example:
Server script, return JSON data:

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// $.getJSON.php
$arr=array("name"=>"zhangsan", "age"=>20);
$jarr=json_encode($arr);
echo $jarr;

Note two points: First: before returning to the client, use the PHP function json_encode to encode the returned data. Second: echo is used to return to the client, not return.
The following is the core client code:

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< ;script language="javascript" type="text/javascript" src="./js/jquery.js">

Since the return value is encoded in JSON in PHP, you must use getJSON to call the PHP file to obtain the data. At the same time, you can notice that the data obtained through getJSON has become an object array, and you can use response.name and response.age to get the return value intuitively.
jquery provides the $.getJSON method, allowing us to implement cross-domain ajax requests, but the content on jqueryAPI is too little. How to use $.getJSON, and what kind of database should be returned by the requesting website so that $.getJSON can obtain it? , I will use a practical example to illustrate below.
The backend is using PHP. One of the main functions of the following code is to provide an interface for appointment registration. The data that needs to be passed in are: user name, contact number and address:

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/*Reservation registration execution interface*/
case "yuyue_interface":
$name = trim($_GET['name']);
$phone = trim($_GET[ 'phone']);
$addr = trim($_GET['addr']);
$dt = date("Y-m-d H:i:s");
$cb = $_GET[ 'callback'];
if($name == "" || $name == NULL){
echo $cb."({code:".json_encode(1)."})";
}elseif($phone == "" || $phone == NULL){
echo $cb."({code:".json_encode(2)."})";
}elseif( $addr == "" || $addr == NULL){
echo $cb."({code:".json_encode(3)."})";
}else{
$db ->execute("insert into tb_yuyue (realname,telphone,danwei,dt,ischeck) values ​​('$name','$phone','$addr','$dt',0)");
echo $cb."({code:".json_encode(0)."})";
}
exit;
break;

Then the front-end processing :

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$(document).ready(function(){
//The following 3 parameters are required for reservation registration
var name = "name"; //varchar type, with a maximum length of 8 digits (4 Chinese characters)
var phone = "phone"; / /varchar type, length is 11 digits
var addr = "addr"; //varchar type, length is up to 500 digits (250 Chinese characters)
$.getJSON("http://request website address/data .php?ac=yuyue_interface&name=" name "&phone=" phone "&addr=" addr "&callback=?", function(data){
if(data.code==1){
//Customized Code
alert("Name cannot be empty");
}else if(data.code==2){
//Custom code
alert("Mobile phone cannot be empty");
}else if(data.code==3){
//Customized code
alert("The unit cannot be empty");
}else{
//Customized Code
alert("Appointment successful");
}
});
});

It should be noted that in the back-end php code, it must Also output the " &callback=? " passed in, such as:

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$cb = $_GET['callback'];
echo $cb."({code:".json_encode(4)."})";

The above is one A simple $.getJSON test. Through this test, we can learn how to use $.getJSON and how to make an interface to allow others to make cross-domain requests.