ajax返回数据类型 text json xml

首先引入类

<?php

class DBDA
{
	public $host = "localhost"; //服务器地址
	public $uid = "root"; //数据库的用户名
	public $pwd = "123"; //数据库的密码
	
	//执行SQL语句，返回相应结果的函数
	//$sql是要执行的SQL语句
	//$type是SQL语句的类型，0代表增删改，1代表查询
	//$db代表要操作的数据库
	public function Query($sql,$type=1,$db="mydb")
	{
		//造连接对象
		$conn = new MySQLi($this->host,$this->uid,$this->pwd,$db);
		
		//判断连接是否成功
		!mysqli_connect_error() or die("连接失败！");
		
		//执行SQL语句
		$result = $conn->query($sql);
		
		//判断SQL语句类型
		if($type==1)
		{
			//如果是查询语句返回结果集的二维数组
			return $result->fetch_all();
		}
		else
		{
			//如果是其他语句，返回true或false
			return $result;
		}
	}
	
	//Ajax调用返回JSON
	public function JsonQuery($sql,$type=1,$db="mydb")
	{
		//定义数据源
		$dsn = "mysql:dbname={$db};host={$this->host}";
		//造pdo对象
		$pdo = new PDO($dsn,"{$this->uid}","{$this->pwd}");

		
		//准备执行SQL语句
		$st = $pdo->prepare($sql);
		
		//执行预处理语句
		if($st->execute())
		{
			if($type==1)
			{
				$attr = $st->fetchAll(PDO::FETCH_ASSOC);
				return json_encode($attr);
			}
			else
			{
				if($st)
				{
					return "OK";
				}
				else
				{
					return "NO";
				}
			}
			
		}
		else
		{
			echo "执行失败！";
		}



	}
	//Ajax调用返回字符串
	public function StrQuery($sql,$type=1,$db="mydb")
	{
		//造连接对象
		$conn = new MySQLi($this->host,$this->uid,$this->pwd,$db);
		
		//判断连接是否成功
		!mysqli_connect_error() or die("连接失败！");
		
		//执行SQL语句
		$result = $conn->query($sql);
		
		//判断SQL语句类型
		if($type==1)
		{
			$attr = $result->fetch_all();
			$str = "";
			//如果是查询语句返回字符串
			for($i=0;$i<count($attr);$i++)
			{
				for($j=0;$j<count($attr[$i]);$j++)
				{
					$str = $str.$attr[$i][$j];
					$str = $str."^";
				}
				$str = substr($str,0,strlen($str)-1);
				$str = $str."|";
			}
			$str = substr($str,0,strlen($str)-1);
			
			return $str;
		}
		else
		{
			//如果是其他语句，返回true或false
			if($result)
			{
				return "OK";
			}
			else
			{
				return "NO";
			}
		}
	}
	
	
}

　　返回类型为json

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>无标题文档</title>
<script src="../jquery-1.11.2.min.js"></script>
</head>

<body>
</body>
<script type="text/javascript">

$(document).ready(function(e) {
    
    $.ajax({
        url:"chuli.php",
        data:{},
        dataType:"JSON",
        type:"POST",
        success: function(data){

            /*    for(key in data)
                {
                    alert(data[key].Name);
                }*/
                
                for(var i=0;i<data.length;i++)
                {
                    alert(data[i].Name);
                }

            }
        
        });
    
    
    
});


</script>
</html>

处理页面

1 <?php
2 
3 include("DBDA.php");
4 $db = new DBDA();
5 
6 $sql = "select * from Nation";
7 
8 echo $db->JsonQuery($sql);

返回类型为text就调用DBDA里的返回字符串的方法

返回类型为xml

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<script src="../jquery-1.11.2.min.js"></script>
<title>无标题文档</title>
</head>

<body>


</body>
<script type="text/javascript">

$(document).ready(function(e) {
   
    $.ajax({
        url:"chulixml.php",
        data:{},
        dataType:"XML",
        type:"POST",
        success: function(data){

            alert($(data).find("Name").eq(0).text());//eq(1)时就查处理页面的n2
            
            }
        
        });
    
    
    
});


</script>

</html>

处理页面

<?php

$str = <<<AA
    <Info>
        <n1>
            <Code>n001</Code>
            <Name>张三</Name>
            <Sex>男</Sex>
        </n1>
        <n2>
            <Code>n002</Code>
            <Name>李四</Name>
            <Sex>女</Sex>
        </n2>
    </Info>
AA;

echo $str;

?>