详解PHP导入导出CSV文件

CREATE TABLE `student` (  
    `id` int(11) NOT NULL auto_increment,  
    `name` varchar(50) NOT NULL,  
    `sex` varchar(10) NOT NULL,  
    `age` smallint(3) NOT NULL default '0',  
    PRIMARY KEY  (`id`)  
) ENGINE=MyISAM  DEFAULT CHARSET=utf8; 

<form id="addform" action="do.php?action=import" method="post" enctype="multipart/form-data"> 
    <p>请选择要导入的CSV文件：<br/><input type="file" name="file"> <input type="submit" 
    class="btn" value="导入CSV"> 
    <input type="button" class="btn" value="导出CSV" onclick="window.location.href='do.php?  
    action=export'"></p> 
</form> 

include_once ("connect.php"); //连接数据库  
$action = $_GET['action'];  
if ($action == 'import') //导入CSV  
{  
    //导入处理  
}elseif($action=='export') //导出CSV  
{  
    //导出处理   
} 

if ($action == 'import') { //导入CSV  
    $filename = $_FILES['file']['tmp_name'];  
    if(emptyempty ($filename))  
    {  
        echo '请选择要导入的CSV文件！';  
        exit;  
    }  
    $handle = fopen($filename, 'r');  
    $result = input_csv($handle); //解析csv  
    $len_result = count($result);  
    if($len_result==0)  
    {  
        echo '没有任何数据！';  
        exit;  
    }  
    for($i = 1; $i < $len_result; $i++) //循环获取各字段值  
    {  
        $name = iconv('gb2312', 'utf-8', $result[$i][0]); //中文转码  
        $sex = iconv('gb2312', 'utf-8', $result[$i][1]);  
        $age = $result[$i][2];  
        $data_values .= "('$name','$sex','$age'),";  
    }  
    $data_values = substr($data_values,0,-1); //去掉最后一个逗号  
    fclose($handle); //关闭指针  
    $query = mysql_query("insert into student (name,sex,age) values $data_values"); //批量插入数据表中  
    if($query)  
    {  
        echo '导入成功！';  
    }else{  
        echo '导入失败！';  
    }  
} 

function input_csv($handle)  
{  
    $out = array ();  
    $n = 0;  
    while ($data = fgetcsv($handle, 10000))  
    {  
        $num = count($data);  
        for ($i = 0; $i < $num; $i++)  
        {  
            $out[$n][$i] = $data[$i];  
        }  
        $n++;  
    }  
    return $out;  
} 

...  
}elseif ($action=='export') //导出CSV  
{  
    $result = mysql_query("select * from student order by id asc");  
    $str = "姓名,性别,年龄\n";  
    $str = iconv('utf-8','gb2312',$str);  
    while($row=mysql_fetch_array($result))  
    {  
        $name = iconv('utf-8','gb2312',$row['name']); //中文转码  
        $sex = iconv('utf-8','gb2312',$row['sex']);  
        $str .= $name.",".$sex.",".$row['age']."\n"; //用引文逗号分开  
    }  
    $filename = date('Ymd').'.csv'; //设置文件名  
    export_csv($filename,$str); //导出  
} 

function export_csv($filename,$data)  
{  
    header("Content-type:text/csv");  
    header("Content-Disposition:attachment;filename=".$filename);  
    header('Cache-Control:must-revalidate,post-check=0,pre-check=0');  
    header('Expires:0');  
    header('Pragma:public');  
    echo $data;  
}