php实现的pdo公共类定义与用法示例
本文实例讲述了php实现的pdo公共类定义与用法。分享给大家供大家参考，具体如下：
db.class.php：
dsn='mysql:host='.$dbHost.';dbname='.$dbName;
$this->dbh=new\PDO($this->dsn,$dbUser,$dbPasswd);
$this->dbh->setAttribute(\PDO::ATTR_EMULATE_PREPARES,false);
$this->dbh->setAttribute(\PDO::ATTR_ERRMODE,\PDO::ERRMODE_EXCEPTION);
$this->dbh->exec('SETcharacter_set_connection='.$dbCharset.';SETcharacter_set_client='.$dbCharset.';SETcharacter_set_results='.$dbCharset);
}catch(Exception$e){
$this->outputError($e->getMessage());
}
}
publicstaticfunctiongetInstance($dbHost,$dbUser,$dbPasswd,$dbName,$dbCharset='utf8'){
if(self::$_instance===null){
self::$_instance=newself($dbHost,$dbUser,$dbPasswd,$dbName,$dbCharset);
}
returnself::$_instance;
}
publicfunctionfetchAll($sql,$params=array()){
try{
$stm=$this->dbh->prepare($sql);
if($stm&&$stm->execute($params)){
return$stm->fetchAll(\PDO::FETCH_ASSOC);
}
}catch(Exception$e){
$this->outputError($e->getMessage());
}
}
publicfunctionfetchOne($sql,$params=array()){
try{
$result=false;
$stm=$this->dbh->prepare($sql);
if($stm&&$stm->execute($params)){
$result=$stm->fetch(\PDO::FETCH_ASSOC);
}
return$result;
}catch(Exception$e){
$this->outputError($e->getMessage());
}
}
publicfunctionfetchColumn($sql,$params=array()){
$result='';
try{
$stm=$this->dbh->prepare($sql);
if($stm&&$stm->execute($params)){
$result=$stm->fetchColumn();
}
return$result;
}catch(Exception$e){
$this->outputError($e->getMessage());
}
}
publicfunctioninsert($table,$params=array(),$returnLastId=true){
$_implode_field='';
$fields=array_keys($params);
$_implode_field=implode(',',$fields);
$_implode_value='';
foreach($fieldsas$value){
$_implode_value.=':'.$value.',';
}
$_implode_value=trim($_implode_value,',');
$sql='INSERTINTO'.$table.'('.$_implode_field.')VALUES('.$_implode_value.')';
try{
$stm=$this->dbh->prepare($sql);
$result=$stm->execute($params);
if($returnLastId){
$result=$this->dbh->lastInsertId();
}
return$result;
}catch(Exception$e){
$this->outputError($e->getMessage());
}
}
publicfunctionupdate($table,$params=array(),$where=null){
$_implode_field='';
$_implode_field_arr=array();
if(empty($where)){
returnfalse;
}
$fields=array_keys($params);
foreach($fieldsas$key){
$_implode_field_arr[]=$key.'='.':'.$key;
}
$_implode_field=implode(',',$_implode_field_arr);
$sql='UPDATE'.$table.'SET'.$_implode_field.'WHERE'.$where;
try{
$stm=$this->dbh->prepare($sql);
$result=$stm->execute($params);
return$result;
}catch(Exception$e){
$this->outputError($e->getMessage());
}
}
publicfunctiondelete($sql,$params=array()){
try{
$stm=$this->dbh->prepare($sql);
$result=$stm->execute($params);
return$result;
}catch(Exception$e){
$this->outputError($e->getMessage());
}
}
publicfunctionexec($sql,$params=array()){
try{
$stm=$this->dbh->prepare($sql);
$result=$stm->execute($params);
return$result;
}catch(Exception$e){
$this->outputError($e->getMessage());
}
}
privatefunctionoutputError($strErrMsg){
thrownewException("MySQLError:".$strErrMsg);
}
publicfunction__destruct(){
$this->dbh=null;
}
}
实例：
12,);
$res=$pdo->fetchOne($sql,$parame);
var_dump($res);
$sql='SELECT*FROMcms_link';
$result=$db->fetchAll($sql);
print_r($result);
//查询记录数量
$sql='SELECTCOUNT(*)FROMcms_link';
$count=$db->fetchColumn($sql);
echo$count;
$data=array(
'siteid'=>1,
'linktype'=>1,
'name'=>'google',
'url'=>'http://www.google.com',
'listorder'=>0,
'elite'=>0,
'passed'=>1,
'addtime'=>time()
);
$lastInsertId=$db->insert('cms_link',$data);
echo$lastInsertId;
//用try
try{
$result=$pdo->insert('news',$essay);
}catch(Exception$e){
error_log($e->getMessage());
error_log($e->getMessage().'in'.__FILE__.'online'.__LINE__);
saveLog('url文章:'.$essay['link'].'数据插入失败
');
continue;
}
$data=array(
'siteid'=>1,
'linktype'=>1,
'name'=>'google',
'url'=>'http://www.google.com',
'listorder'=>0,
'elite'=>0,
'passed'=>1,
'addtime'=>time()
);
$db->insert('cms_link',$data);
$sql='DELETEFROMcms_linkWHERElinkid=4';
$result=$db->delete($sql);
var_dump($result);
更多关于PHP相关内容感兴趣的读者可查看本站专题：《PHP基于pdo操作数据库技巧总结》、《php+Oracle数据库程序设计技巧总结》、《PHP+MongoDB数据库操作技巧大全》、《php面向对象程序设计入门教程》、《php字符串(string)用法总结》、《php+mysql数据库操作入门教程》及《php常见数据库操作技巧汇总》
希望本文所述对大家PHP程序设计有所帮助。