CVS文件的导入和导出php类代码，通过这个自定义的php类可以实现数据库的数据和CVS文件的转换

<?php
/**
 * CSV 文件处理类
 */
class Csv{
    public $csv_array; //csv数组数据
    public $csv_str;  //csv文件数据
      
    public function __construct($param_arr, $column){
        $this->csv_array = $param_arr;
        $this->path = $path;
        $this->column = $column;
    }
      
    /**
     * 导出
     * */
    public function export(){
        if(empty($this->csv_array) || empty($this->column)){
            return false;
        }
        $param_arr = $this->csv_array;
        unset($this->csv_array);
        $export_str = implode(',',$param_arr['nav'])."n";
        unset($param_arr['nav']);
        //组装数据
        foreach($param_arr as $k=>$v){
            foreach($v as $k1=>$v1){
                $export_str .= implode(',',$v1)."n";
            }
        }
        //将$export_str导出
        header( "Cache-Control: public" );
        header( "Pragma: public" );
        header("Content-type:application/vnd.ms-excel");
        header("Content-Disposition:attachment;filename=txxx.csv");
        header('Content-Type:APPLICATION/OCTET-STREAM');
        ob_start();     
      //  $file_str=  iconv("utf-8",'gbk',$export_str);
        ob_end_clean();
        echo $export_str;
    }
      
    /**
     * 导入
     * */
    public function import($path,$column = 3){
        $flag = flase;
        $code = 0;
        $msg = '未处理';
        $filesize = 1; //1MB
        $maxsize = $filesize * 1024 * 1024;
        $max_column = 1000;
  
        //检测文件是否存在
        if($flag === flase){
            if(!file_exists($path)){
                $msg = '文件不存在';
                $flag = true;
            }
        }
        //检测文件格式
        if($flag === flase){
            $ext = preg_replace("/.*.([^.]+)/","$1",$path);
            if($ext != 'csv'){
                $msg = '只能导入CSV格式文件';
                $flag = true;
            }
        }
          
        //检测文件大小
        if($flag === flase){
            if(filesize($path)>$maxsize){
                $msg = '导入的文件不得超过'.$maxsize.'B文件';
                $flag = true;
            }
        }
  
        //读取文件
        if($flag == flase){
            $row = 0;
            $handle = fopen($path,'r');
            $dataArray = array();
            while($data = fgetcsv($handle,$max_column,",")){
                $num = count($data);
                if($num < $column){
                    $msg = '文件不符合规格真实有：'.$num.'列数据';
                    $flag = true;
                    break;
                }
  
                if($flag === flase){
                    for($i=0;$i<3;$i++){
                        if($row == 0){
                            break;
                        }
                        //组建数据
                        $dataArray[$row][$i] = $data[$i];
                    }
                }
                $row++;
            }
        }
          
        return $dataArray;
    }
}
  
$param_arr = array(
                'nav'=>array('用户名','密码','邮箱'),
                array(0=>array('xiaohai1','123456','xiaohai1@zhongsou.com'),
                      1=>array('xiaohai2','213456','xiaohai2@zhongsou.com'),
                      2=>array('xiaohai3','123456','xiaohai3@zhongsou.com')
                ));
                  
$column = 3;
$csv = new Csv($param_arr, $column);
//$csv->export();
$path = 'C:Documents and SettingsAdministratorLocal SettingsTemptxxx.csv';
$import_arr = $csv->import($path,3);
var_dump($import_arr);
  
?>