}

}

function fetch_one_array($sql) {
//获取单条记录
$this->query($sql);
Return mysql_fetch_array($this->result,MYSQL_ASSOC);

}

function fetch_array($sql) {
//获取多条记录
$this->rows_array = '';
$this->query($sql);
while($rs=mysql_fetch_array($this->result,MYSQL_ASSOC)) $this->r
ows_array[]=$rs;
Return $this->rows_array;

}

function udiquery($sql){
//sql添加、更新、删除操作
$this->query($sql);
$this->rows_num = mysql_affected_rows();
if(mysql_errno() == 0)return $this->rows_num;
else return '';

}

function get_insert_id() {
//返回新增的自增ID
return mysql_insert_id();

}

function numrows($sql) {
//返回总记录数
$this->query($sql);
Return mysql_num_rows($this->result);

}

function closerst() {
//清空记录集
$this->rows_array='';
mysql_free_result($this->result);

}
function closedb() {
//关闭链接
$this->closerst;
mysql_close($this->conn);

}

}
?>
db_name}.{$this->tbl_name}";
if( $where_str ) $sql .= " Where {$where_str}";

if ($b_select_count)
{
$count_sql = preg_replace('|Select(.*)FROM|i','Select COUNT(*
) AS count FROM', $sql);
$tmp = $this->fetch_one_array($count_sql);
return $tmp["count"]*1;

}

if( $group_by ) $sql .= " GROUP BY {$group_by}";
if ($order_by)
{
check_order_by($order_by);
$sql .= " ORDER BY ".$order_by;
}

if ($limit)
{
check_limit_str($limit);
$sql .= " LIMIT ".$limit;
}

$rows = $this->fetch_array($sql);
return $rows;

}

/**
* 查询指定结果函数
* @access public
* @param string $where_str 查询条件
* @param string $select_str 查询字段
* @return array
*/
public function get_table_row_info($where_str='', $select_s
tr = "*")
{
$sql = " Select {$select_str} FROM {$this->db_name}.{$thi
s->tbl_name}";
if( $where_str ) $sql .= " Where {$where_str} LIMIT 0,1";
$ret_arr = $this->fetch_one_array($sql);
return $ret_arr;

}

/**
* 插入数据函数
* @access public
* @param array $insert_arr 数据数组
* @param string $insert_type 插入数据方式：REPLACE替换插入，IGNORE
防止重复插入
* @return int $id 最新插入ID
*/
public function _insert_table_filed($insert_arr, $insert_type = "")
{
$insert_str = arr_to_update_str($insert_arr);
if ( $insert_type == "REPLACE" )$sql = "REPLACE INTO {$this->d
b_name}.{$this->tbl_name} SET {$insert_str}";
elseif ( $insert_type == "IGNORE" )$sql = "Insert IGNORE INTO {
$this->db_name}.{$this->tbl_name} SET {$insert_str}";
else $sql = "Insert INTO {$this->db_name}.{$this->tbl_name} SE
T {$insert_str}";
$this->udiquery($sql);
$id = $this->get_insert_id();
return $id;

}

/**
* 删除表数据
* @access public
* @param string $where_str 删除条件
* @return bool
*/
public function del_table_flied($where_str)
{
if( $where_str ){

$sql = " Delete FROM {$this->db_name}.{$this->tbl_name} Wh
ere {$where_str}";
$ret = $this->udiquery($sql);
return $ret;

}
else {

exit("执行".__CLASS__."类中".__FUNCTION__."方法错误:sql的whe
re_str条件不能为空 line ".__LINE__.' IN '.__FILE__);

}

}

/**
* 更新表数据函数
*
* @access public
* @param array $update_arr 要更新的字段数组
* @param string $update_tbl 要更新的表名
* @param string $where_str 要更新的条件
*/
public function update_table_field( $update_arr, $where_str )
{

if( !emptyempty($update_arr)&&!emptyempty($where_str) ){

$update_str = arr_to_update_str($update_arr);
$sql = " Update {$this->db_name}.{$this->tbl_name} S
ET $update_str Where {$where_str}";
$ret = $this->udiquery($sql);
return $ret;

}

}
}
?>

");

}

}
if (!function_exists("arr_to_update_str"))
//将数组转换为键对值的字符
{
function arr_to_update_str($data_arr)
{
if( !emptyempty($data_arr) ) {

foreach ($data_arr as $key=>$val)
{
$sql_str_arr[] = "{$key}='{$val}'";

}

$sql_str = implode(',',$sql_str_arr);
return $sql_str;
}
else{

exit('函数'.__FUNCTION__.'执行时产生错误：data_arr 数组为空。l
ine '.__LINE__.' IN '.__FILE__);

}
}
}

if (!function_exists("check_limit_str"))
//检测 limit 是否合法
{
function check_limit_str($limitstr)
{
$limitstr = trim($limitstr);
$limitstr = str_replace(" ","",$limitstr);
$chech_status = preg_match("/^\d+,\d+$/i",$limitstr);
if (!$chech_status) exit('函数'.__FUNCTION__.'执行时产生错误：非
法的limit语句。limit[{$limitstr}] line '.__LINE__.' IN '.__FILE__);
return $chech_status;

}
}

if (!function_exists("check_order_by"))
//检测 order by 是否合法
{
function check_order_by($orderby)
{
$orderby = trim($orderby);
$c = preg_match("/^([ ,A-Za-z0-9_])* [DESC|ASC]+$/i",$o
rderby);
if (!$c) exit('函数'.__FUNCTION__.'执行时产生错误：非法的orderby语
句。order by[{$orderby}] line '.__LINE__.' IN '.__FILE__);
return $c;

}
}

if (!function_exists("aasort"))
{
//二维数组排序 使用方法 $array 传入的数组 $args 需要排序的列 前缀为 + 的是升
序 ，-为降序。例：aasort($array,'-id')
function aasort($array, $args)
{
$sort_rule="";
foreach($args as $arg)
{
$order_field = substr($arg, 1, strlen($arg));
foreach($array as $array_row)
{
$sort_array[$order_field][] = $array_row[$order_field];
}
$sort_rule .= '$sort_array['.$order_field.'], '.($arg[0] =
= "+" ? SORT_ASC : SORT_DESC).',';
}
eval ("array_multisort($sort_rule".' &$array);');
}
}
?>
get_table_row_info($where_str);

}

}

}
$students_obj = new students_class();
var_dump($students_obj->get_students_list_by_id(1));
?>
[/code]