使用json数据格式进行ajax回调

//创建json数据格式
var people =  { "programmers": [    { "firstName": "Brett", "lastName":"McLaughlin",
"email": "[email protected]" },    { "firstName": "Jason", "lastName":"Hunter",
"email": "[email protected]" },    { "firstName": "Elliotte", "lastName":"Harold",
"email": "[email protected]" }   ],  "authors": [    { "firstName": "Isaac", 
"lastName": "Asimov", "genre": "science fiction" },    { "firstName": "Tad", 
"lastName": "Williams", "genre": "fantasy" },    { "firstName": "Frank", 
"lastName": "Peretti", "genre": "christian fiction" }   ],  "musicians": [    
{ "firstName": "Eric", "lastName": "Clapton", "instrument": "guitar" },   
{ "firstName": "Sergei", "lastName": "Rachmaninoff", "instrument": "piano" }   ]  };

//发送json数据
var url = "organizePeople.php?people=" + escape(people.toJSONString());
xmlHttp.open("GET", url, true);
xmlHttp.onreadystatechange = updatePage;
xmlHttp.send(null);

 这种做法已经是可以了，但是传送的url参数可能会太长，因为json对象我们不肯定有多少数据

 

所以应该考虑用post，而放弃用get

 

var url = "organizePeople.php?timeStamp=" + new Date().getTime();
request.open("POST", url, true);
request.onreadystatechange = updatePage;
request.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");
request.send(people.toJSONString());

 

application/x-www-form-urlencoded，它让服务器知道现在发送的是文本，正如它从常规的 HTML 表单中得到的一样。