我们先准备mysql数据表,假设项目中有一张记录学生信息的表student,并有id,name,sex,age分别记录学生的姓名、性别、年龄等信息。
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;
我们还需要一个html交互页面,放置导入表单和导出按钮。
<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>
选择好本地csv文件后,点击导入,提交到do.php?action=import处理,而点击导出按钮则请求地址do.php?action=export进行数据导出处理。
1.导入CSV
do.php需要根据get过来的参数,分别处理导入和导出过程,php结构如下:
include_once ("connect.php"); //连接数据库$action = $_GET['action'];if ($action == 'import') { //导入CSV //导入处理} elseif ($action=='export') { //导出CSV //导出处理}
导入CSV处理流程:校验csv文件合法性(本文忽略)->打开读入并解析csv文件中的字段->循环获取各字段值->批量添加到数据表中->完成。
if ($action == 'import') { //导入CSV $filename = $_FILES['file']['tmp_name']; if (empty ($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!'; }}
注意php自带的fgetcsv函数可以轻松处理csv,使用该函数可以从文件指针中读入一行并解析CSV字段。下面的函数将csv文件字段解析并以数组的形式返回。
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 $out;}
此外在导入到数据库中时,我们采用的是批量插入而不是一条条插入的,因此在构建SQL语句时,要稍作处理,见代码。
2.导出CSV
我们知道csv文件是由逗号分割符组成的纯文本文件,你可以用excel打开,效果跟xls表个一样。
导出CSV处理流程:读取学生信息表->循环记录构建逗号分隔的字段信息->设置header信息->导出文件(下载)到本地
...} elseif ($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,$str); //导出}
要将数据导出到本地即下在,需要修改header信息,代码如下:
function export_csv($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;}
注意导入和导出的过程中,因为我们使用的是统一UTF-8编码,遇到中文字符一定要记得转码,否则可能会出现中文乱码的情况。

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