set_time_limit(0);
$config['upload_path'] =  'datauploads/';
$config['allowed_types'] = '*'; // CSV|csv|xlsx|xls
$config['max_size']	= '0';
$config['max_width']  = '0';
$config['max_height']  = '0';
$config['overwrite']  = TRUE;

$this->load->library('upload', $config);
if(!$this->upload->do_upload('file_upload'))
{
	$error = array('error' => $this->upload->display_errors());
	print_r($error);
}
else
{
	$file_name = $this->upload->file_name;
	$datas = array('upload_data' => $this->upload->data());
	$handle = fopen(base_url()."datauploads/$file_name", "r"); 			
	$fp = $handle;
	$BufferString= @fgets($fp ,4096);
	$BufferString   = explode("\n",$BufferString);
	$childDropdown = array();
	$childDropdownArr = $this->dform_model->edit_field($modId,$recId);
	$childDropdown = explode("|",$childDropdownArr['def_value']);

	while (($datas = fgetcsv($handle,1024*30, ",")) !== FALSE) 
	{		
		$displayName = $datas[0];
		$databaseValue = $datas[1]; 

		if(!in_array($databaseValue,$childDropdown[$displayName]))
		$childDropdown[$displayName][] = $databaseValue;					
	}
}

在这里，我编写了一些代码，用表的def|value列中的现有值更新新的excel值，我有这样的def|value值（0，us，us，| 0，monali，monali，|），在这里，我需要从文本中分解0和|。我将值分解为$childdropdown=explode（“|”，$childdropdownarr['def_value']）；但它不适用于爆炸两个值。如何做到这一点使用codeigniter可以任何一个请帮助我。。