高效mongodb的php分页类（不使用skip）

//MongoDB操作类
classDB
{

 private$CI;
 private$config_file="MongoDB";

 private$connection;
 private$db;
 private$connection_string;

 private$collection="";
 private$host;
 private$port;
 private$user;
 private$pass;
 private$dbname;
 private$key;
 private$persist;
 private$persist_key;

 private$selects=array();
 private$wheres=array();
 private$sorts=array();
 private$page_sorts=array();

 private$limit=999999;
 private$offset=0;
 

 /**
 *--------------------------------------------------------------------------------
 *CONSTRUCTOR
 *--------------------------------------------------------------------------------
 *
 *AutomaticallycheckiftheMongoPECLextensionhasbeeninstalled/enabled.
 *GeneratetheconnectionstringandestablishaconnectiontotheMongoDB.
 */

 publicfunction__construct($MONGODB_CONFIG)
 {
 if(!class_exists("Mongo"))
 {
  show_error("TheMongoDBPECLextensionhasnotbeeninstalledorenabled",500);
 }
 /**
       $config["mongo_host"]="221.234.43.144";
       $config["mongo_port"]=27017;
       $config["mongo_db"]="test";
       $config["mongo_user"]="";
       $config["mongo_pass"]="";
       $config["mongo_persist"]=TRUE;
        *
        */
 $this->connection_string($MONGODB_CONFIG);
 $this->connect();
 }

 

 /**
 *--------------------------------------------------------------------------------
 *Switch_db
 *--------------------------------------------------------------------------------
 *
 *Switchfromdefaultdatabasetoadifferentdb
 */

 publicfunctionswitch_db($database="")
 {
 if(empty($database))
 {
  show_error("ToswitchMongoDBdatabases,anewdatabasenamemustbespecified",500);
 }
 $this->dbname=$database;
 try
 {
  $this->db=$this->connection->{$this->dbname};
  return(TRUE);
 }
 catch(Exception$e)
 {
  show_error("UnabletoswitchMongoDatabases:{$e->getMessage()}",500);
 }
 }

 /**
 *--------------------------------------------------------------------------------
 *SELECTFIELDS
 *--------------------------------------------------------------------------------
 *
 *DeterminewhichfieldstoincludeORwhichtoexcludeduringthequeryprocess.
 *Currently,includingandexcludingatthesametimeisnotavailable,sothe
 *$includesarraywilltakeprecedenceoverthe$excludesarray. Ifyouwantto
 *onlychoosefieldstoexclude,leave$includesanemptyarray().
 *
 *@usage:$this->mongo_db->select(array("foo","bar"))->get("foobar");
 */

 publicfunctionselect($includes=array(),$excludes=array())
 {
  if(!is_array($includes))
  {
   $includes=array();
  }

  if(!is_array($excludes))
  {
   $excludes=array();
  }

  if(!empty($includes))
  {
   foreach($includesas$col)
   {
    $this->selects[$col]=1;
   }
  }
  else
  {
   foreach($excludesas$col)
   {
    $this->selects[$col]=0;
   }
  }
  return($this);
 }

 /**
 *--------------------------------------------------------------------------------
 *WHEREPARAMETERS
 *--------------------------------------------------------------------------------
 *
 *Getthedocumentsbasedonthesesearchparameters. The$wheresarrayshould
 *beanassociativearraywiththefieldasthekeyandthevalueasthesearch
 *criteria.
 *
 *@usage=$this->mongo_db->where(array("foo"=>"bar"))->get("foobar");
 */

 publicfunctionwhere($wheres=array())
 {
  foreach($wheresas$wh=>$val)
  {
   $this->wheres[$wh]=$val;
  }
  return($this);
 }

 /**
 *--------------------------------------------------------------------------------
 *WHERE_INPARAMETERS
 *--------------------------------------------------------------------------------
 *
 *Getthedocumentswherethevalueofa$fieldisinagiven$inarray().
 *
 *@usage=$this->mongo_db->where_in("foo",array("bar","zoo","blah"))->get("foobar");
 */

 publicfunctionwhere_in($field="",$in=array())
 {
  $this->where_init($field);
  $this->wheres[$field]["$in"]=$in;
  return($this);
 }

 /**
 *--------------------------------------------------------------------------------
 *WHERE_NOT_INPARAMETERS
 *--------------------------------------------------------------------------------
 *
 *Getthedocumentswherethevalueofa$fieldisnotinagiven$inarray().
 *
 *@usage=$this->mongo_db->where_not_in("foo",array("bar","zoo","blah"))->get("foobar");
 */

 publicfunctionwhere_not_in($field="",$in=array())
 {
  $this->where_init($field);
  $this->wheres[$field]["$nin"]=$in;
  return($this);
 }

 /**
 *--------------------------------------------------------------------------------
 *WHEREGREATERTHANPARAMETERS
 *--------------------------------------------------------------------------------
 *
 *Getthedocumentswherethevalueofa$fieldisgreaterthan$x
 *
 *@usage=$this->mongo_db->where_gt("foo",20);
 */

 publicfunctionwhere_gt($field="",$x)
 {
  $this->where_init($field);
  $this->wheres[$field]["$gt"]=$x;
  return($this);
 }

 /**
 *--------------------------------------------------------------------------------
 *WHEREGREATERTHANOREQUALTOPARAMETERS
 *--------------------------------------------------------------------------------
 *
 *Getthedocumentswherethevalueofa$fieldisgreaterthanorequalto$x
 *
 *@usage=$this->mongo_db->where_gte("foo",20);
 */

 publicfunctionwhere_gte($field="",$x)
 {
  $this->where_init($field);
  $this->wheres[$field]["$gte"]=$x;
  return($this);
 }

 /**
 *--------------------------------------------------------------------------------
 *WHERELESSTHANPARAMETERS
 *--------------------------------------------------------------------------------
 *
 *Getthedocumentswherethevalueofa$fieldislessthan$x
 *
 *@usage=$this->mongo_db->where_lt("foo",20);
 */

 publicfunctionwhere_lt($field="",$x)
 {
  $this->where_init($field);
  $this->wheres[$field]["$lt"]=$x;
  return($this);
 }

 /**
 *--------------------------------------------------------------------------------
 *WHERELESSTHANOREQUALTOPARAMETERS
 *--------------------------------------------------------------------------------
 *
 *Getthedocumentswherethevalueofa$fieldislessthanorequalto$x
 *
 *@usage=$this->mongo_db->where_lte("foo",20);
 */

 publicfunctionwhere_lte($field="",$x)
 {
  $this->where_init($field);
  $this->wheres[$field]["$lte"]=$x;
  return($this);
 }

 /**
 *--------------------------------------------------------------------------------
 *WHEREBETWEENPARAMETERS
 *--------------------------------------------------------------------------------
 *
 *Getthedocumentswherethevalueofa$fieldisbetween$xand$y
 *
 *@usage=$this->mongo_db->where_between("foo",20,30);
 */

 publicfunctionwhere_between($field="",$x,$y)
 {
  $this->where_init($field);
  $this->wheres[$field]["$gte"]=$x;
  $this->wheres[$field]["$lte"]=$y;
  return($this);
 }

 /**
 *--------------------------------------------------------------------------------
 *WHEREBETWEENANDNOTEQUALTOPARAMETERS
 *--------------------------------------------------------------------------------
 *
 *Getthedocumentswherethevalueofa$fieldisbetweenbutnotequalto$xand$y
 *
 *@usage=$this->mongo_db->where_between_ne("foo",20,30);
 */

 publicfunctionwhere_between_ne($field="",$x,$y)
 {
  $this->where_init($field);
  $this->wheres[$field]["$gt"]=$x;
  $this->wheres[$field]["$lt"]=$y;
  return($this);
 }

 /**
 *--------------------------------------------------------------------------------
 *WHERENOTEQUALTOPARAMETERS
 *--------------------------------------------------------------------------------
 *
 *Getthedocumentswherethevalueofa$fieldisnotequalto$x
 *
 *@usage=$this->mongo_db->where_between("foo",20,30);
 */

 publicfunctionwhere_ne($field="",$x)
 {
  $this->where_init($field);
  $this->wheres[$field]["$ne"]=$x;
  return($this);
 }

 /**
 *--------------------------------------------------------------------------------
 *WHEREOR
 *--------------------------------------------------------------------------------
 *
 *Getthedocumentswherethevalueofa$fieldisinoneormorevalues
 *
 *@usage=$this->mongo_db->where_or("foo",array("foo","bar","blegh");
 */

 publicfunctionwhere_or($field="",$values)
 {
  $this->where_init($field);
  $this->wheres[$field]["$or"]=$values;
  return($this);
 }

 /**
 *--------------------------------------------------------------------------------
 *WHEREAND
 *--------------------------------------------------------------------------------
 *
 *Getthedocumentswheretheelementsmatchthespecifiedvalues
 *
 *@usage=$this->mongo_db->where_and(array("foo"=>1,"b"=>"someexample");
 */

 publicfunctionwhere_and($elements_values=array()){
  foreach($elements_valuesas$element=>$val){
   $this->wheres[$element]=$val;
  }
  return($this);
 }

 /**
 *--------------------------------------------------------------------------------
 *WHEREMOD
 *--------------------------------------------------------------------------------
 *
 *Getthedocumentswhere$field%$mod=$result
 *
 *@usage=$this->mongo_db->where_mod("foo",10,1);
 */

 publicfunctionwhere_mod($field,$num,$result){
  $this->where_init($field);
  $this->wheres[$field]["$mod"]=array($num,$result);
  return($this);
 }

 /**
 *--------------------------------------------------------------------------------
 *Wheresize
 *--------------------------------------------------------------------------------
 *
 *Getthedocumentswherethesizeofafieldisinagiven$sizeint
 *
 *@usage:$this->mongo_db->where_size("foo",1)->get("foobar");
 */

 publicfunctionwhere_size($field="",$size="")
 {
 $this->_where_init($field);
 $this->wheres[$field]["$size"]=$size;
 return($this);
 }

 /**
 *--------------------------------------------------------------------------------
 *LIKEPARAMETERS
 *--------------------------------------------------------------------------------
 *
 *Getthedocumentswherethe(string)valueofa$fieldislikeavalue.Thedefaults
 *allowforacase-insensitivesearch.
 *
 *@param$flags
 *Allowsforthetypicalregularexpressionflags:
 * i=caseinsensitive
 * m=multiline
 * x=cancontaincomments
 * l=locale
 * s=dotall,"."matcheseverything,includingnewlines
 * u=matchunicode
 *
 *@param$enable_start_wildcard
 *IfsettoanythingotherthanTRUE,astartinglinecharacter"^"willbeprepended
 *tothesearchvalue,representingonlysearchingforavalueatthestartof
 *anewline.
 *
 *@param$enable_end_wildcard
 *IfsettoanythingotherthanTRUE,anendinglinecharacter"$"willbeappended
 *tothesearchvalue,representingonlysearchingforavalueattheendof
 *aline.
 *
 *@usage=$this->mongo_db->like("foo","bar","im",FALSE,TRUE);
 */

 publicfunctionlike($field="",$value="",$flags="i",$enable_start_wildcard=TRUE,$enable_end_wildcard=TRUE)
 {
  $field=(string)trim($field);
  $this->where_init($field);
  $value=(string)trim($value);
  $value=quotemeta($value);

  if($enable_start_wildcard!==TRUE)
  {
   $value="^".$value;
  }

  if($enable_end_wildcard!==TRUE)
  {
   $value.="$";
  }

  $regex="/$value/$flags";
  $this->wheres[$field]=newMongoRegex($regex);
  return($this);
 }

 /**
 *--------------------------------------------------------------------------------
 *ORDERBYPARAMETERS
 *--------------------------------------------------------------------------------
 *
 *Sortthedocumentsbasedontheparameterspassed.Tosetvaluestodescendingorder,
 *youmustpassvaluesofeither-1,FALSE,"desc",or"DESC",elsetheywillbe
 *setto1(ASC).
 *
 *@usage=$this->mongo_db->where_between("foo",20,30);
 */

 publicfunctionorder_by($fields=array())
 {
  foreach($fieldsas$col=>$val)
  {
   if($val==-1||$val===FALSE||strtolower($val)=="desc")
   {
    $this->sorts[$col]=-1;
   }
   else
   {
    $this->sorts[$col]=1;
   }
  }
  return($this);
 }

 /**
 *--------------------------------------------------------------------------------
 *LIMITDOCUMENTS
 *--------------------------------------------------------------------------------
 *
 *Limittheresultsetto$xnumberofdocuments
 *
 *@usage=$this->mongo_db->limit($x);
 */

 publicfunctionlimit($x=99999){
  if($x!==NULL&&is_numeric($x)&&$x>=1)
  {
   $this->limit=(int)$x;
  }
  return($this);
 }

 /**
 *--------------------------------------------------------------------------------
 *OFFSETDOCUMENTS
 *--------------------------------------------------------------------------------
 *
 *Offsettheresultsettoskip$xnumberofdocuments
 *
 *@usage=$this->mongo_db->offset($x);
 */

 publicfunctionoffset($x=0)
 {
  if($x!==NULL&&is_numeric($x)&&$x>=1)
  {
   $this->offset=(int)$x;
  }
  return($this);
 }

 /**
 *--------------------------------------------------------------------------------
 *GET_WHERE
 *--------------------------------------------------------------------------------
 *
 *Getthedocumentsbaseduponthepassedparameters
 *
 *@usage=$this->mongo_db->get_where("foo",array("bar"=>"something"));
 */

 publicfunctionget_where($collection="",$where=array(),$limit=99999)
 {
  return($this->where($where)->limit($limit)->get($collection));
 }

 /**
 *--------------------------------------------------------------------------------
 *GET
 *--------------------------------------------------------------------------------
 *
 *Getthedocumentsbaseduponthepassedparameters
 *
 *@usage=$this->mongo_db->get("foo",array("bar"=>"something"));
 */

 publicfunctionget($collection="")
 {
  if(empty($collection))
  {
   show_error("InordertoretreivedocumentsfromMongoDB,acollectionnamemustbepassed",500);
  }
  $results=array();
  $documents=$this->db->{$collection}->find($this->wheres,$this->selects)->limit((int)$this->limit)->skip((int)$this->offset)->sort($this->sorts);

  $returns=array();

  foreach($documentsas$doc):
   $returns[]=$doc;
  endforeach;
 $this->clear();
  return($returns);

 }

 /**
 *--------------------------------------------------------------------------------
 *COUNT
 *--------------------------------------------------------------------------------
 *
 *Countthedocumentsbaseduponthepassedparameters
 *
 *@usage=$this->mongo_db->get("foo");
 */

 publicfunctioncount($collection="")
 {
  if(empty($collection))
  {
   show_error("InordertoretreiveacountofdocumentsfromMongoDB,acollectionnamemustbepassed",500);
  }
  $count=$this->db->{$collection}->find($this->wheres)->limit((int)$this->limit)->skip((int)$this->offset)->count();
  $this->clear();
  return($count);
 }

 /**
 *自增ID实现
 *returninsert_id
 */
 privatefunctioninsert_inc($table)
 {
 $update=array("$inc"=>array("id"=>1));
 $query=array("table"=>$table);
 $command=array(
 "findandmodify"=>"_increase",
 "update"=>$update,
 "query"=>$query,
 "new"=>true,
 "upsert"=>true
 );
 $id=$this->db->command($command);
 return$id["value"]["id"];
 }

 /**
 *--------------------------------------------------------------------------------
 *INSERT
 *--------------------------------------------------------------------------------
 *
 *Insertanewdocumentintothepassedcollection
 *
 *@usage=$this->mongo_db->insert("foo",$data=array());
 */

 publicfunctioninsert($collection="",$data=array()){
  if(empty($collection))
  {
   show_error("NoMongocollectionselectedtoinsertinto",500);
  }

  if(count($data)==0||!is_array($data))
  {
   show_error("NothingtoinsertintoMongocollectionorinsertisnotanarray",500);
  }

  try
  {
  $inc=$this->insert_inc($collection);
  $data["_id"]=$inc;
   $result=$this->db->{$collection}->insert($data,array("fsync"=>TRUE));
   if($result["ok"]||$result){
   returntrue;
  }
  else{
   returnfalse;
  }
  }
  catch(MongoCursorException$e)
  {
   show_error("InsertofdataintoMongoDBfailed:{$e->getMessage()}",500);
  }

 }

 /**
 *--------------------------------------------------------------------------------
 *UPDATE
 *--------------------------------------------------------------------------------
 *
 *Updateadocumentintothepassedcollection
 *
 *@usage=$this->mongo_db->update("foo",$data=array());
 */

 publicfunctionupdate($collection="",$data=array(),$flage=false)
 {
  if(empty($collection))
  {
   show_error("NoMongocollectionselectedtoupdate",500);
 }
  if(count($data)==0||!is_array($data))
  {
   show_error("NothingtoupdateinMongocollectionorupdateisnotanarray",500);
 }
 unset($data["_id"]);
 if($flage){
  $arr=$this->wheres;
  unset($arr["_id"]);
  if(is_array($arr)){
   foreach($arras$key=>$w){
    unset($data[$key]);
   }
  }
 }
 try
  {
   $res=$this->db->{$collection}->update($this->wheres,array("$set"=>$data),array("fsync"=>TRUE,"multiple"=>FALSE));
  $this->clear();
  return$res;
  } 
  catch(MongoCursorException$e)
  {
   show_error("UpdateofdataintoMongoDBfailed:{$e->getMessage()}",500);
  }

 }

 /**
 *--------------------------------------------------------------------------------
 *UPDATE_ALL
 *--------------------------------------------------------------------------------
 *
 *Insertanewdocumentintothepassedcollection
 *
 *@usage=$this->mongo_db->update_all("foo",$data=array());
 */

 publicfunctionupdate_all($collection="",$data=array()){
  if(empty($collection))
  {
   show_error("NoMongocollectionselectedtoupdate",500);
  }

  if(count($data)==0||!is_array($data))
  {
   show_error("NothingtoupdateinMongocollectionorupdateisnotanarray",500);
  }

  try
  {
   $this->db->{$collection}->update($this->wheres,array("$set"=>$data),array("fsync"=>TRUE,"multiple"=>TRUE));
  $this->clear();
   return(TRUE);
  }
  catch(MongoCursorException$e)
  {
   show_error("UpdateofdataintoMongoDBfailed:{$e->getMessage()}",500);
  }

 }

 /**
 *--------------------------------------------------------------------------------
 *DELETE
 *--------------------------------------------------------------------------------
 *
 *deletedocumentfromthepassedcollectionbaseduponcertaincriteria
 *
 *@usage=$this->mongo_db->delete("foo",$data=array());
 */

 publicfunctiondelete($collection,$where)
 {
  if(empty($collection))
  {
   show_error("NoMongocollectionselectedtodeletefrom",500);
  }
 if(!$where){
  show_error("Nodatainputtodelete",500);
 }
  try
  {
  $this->wheres=$where;
   $this->db->{$collection}->remove($this->wheres);
  $this->clear();
   return(TRUE);
  }
  catch(MongoCursorException$e)
  {
   show_error("DeleteofdataintoMongoDBfailed:{$e->getMessage()}",500);
  }

 }

 /**
 *--------------------------------------------------------------------------------
 *DELETE_ALL
 *--------------------------------------------------------------------------------
 *
 *Deletealldocumentsfromthepassedcollectionbaseduponcertaincriteria
 *
 *@usage=$this->mongo_db->delete_all("foo",$data=array());
 */

 publicfunctiondelete_all($collection="")
 {
    if(empty($collection))
    {
     show_error("NoMongocollectionselectedtodeletefrom",500);
   }

  try
  {
   $this->db->{$collection}->remove($this->wheres,array("fsync"=>TRUE,"justOne"=>FALSE));
  $this->clear();
   return(TRUE);
  }
  catch(MongoCursorException$e)
  {
   show_error("DeleteofdataintoMongoDBfailed:{$e->getMessage()}",500);
  }

 }

 /**
 *--------------------------------------------------------------------------------
 *ADD_INDEX
 *--------------------------------------------------------------------------------
 *
 *Ensureanindexofthekeysinacollectionwithoptionalparameters.Tosetvaluestodescendingorder,
 *youmustpassvaluesofeither-1,FALSE,"desc",or"DESC",elsetheywillbe
 *setto1(ASC).
 *
 *@usage=$this->mongo_db->add_index($collection,array("first_name"=>"ASC","last_name"=>-1),array("unique"=>TRUE));
 */

 publicfunctionadd_index($collection="",$keys=array(),$options=array())
 {
 if(empty($collection))
 {
   show_error("NoMongocollectionspecifiedtoaddindexto",500);
  }

  if(empty($keys)||!is_array($keys))
  {
   show_error("IndexcouldnotbecreatedtoMongoDBCollectionbecausenokeyswerespecified",500);
   }

  foreach($keysas$col=>$val)
  {
   if($val==-1||$val===FALSE||strtolower($val)=="desc")
   {
    $keys[$col]=-1;
   }
   else
   {
    $keys[$col]=1;
   }
  }

  if($this->db->{$collection}->ensureIndex($keys,$options)==TRUE)
  {
   $this->clear();
   return($this);
  }
  else
  {
   show_error("AnerroroccuredwhentryingtoaddanindextoMongoDBCollection",500);
 }
 }

 /**
 *--------------------------------------------------------------------------------
 *REMOVE_INDEX
 *--------------------------------------------------------------------------------
 *
 *Removeanindexofthekeysinacollection.Tosetvaluestodescendingorder,
 *youmustpassvaluesofeither-1,FALSE,"desc",or"DESC",elsetheywillbe
 *setto1(ASC).
 *
 *@usage=$this->mongo_db->remove_index($collection,array("first_name"=>"ASC","last_name"=>-1));
 */

 publicfunctionremove_index($collection="",$keys=array())
 {
 if(empty($collection))
 {
   show_error("NoMongocollectionspecifiedtoremoveindexfrom",500);
  }

  if(empty($keys)||!is_array($keys))
  {
   show_error("IndexcouldnotberemovedfromMongoDBCollectionbecausenokeyswerespecified",500);
  }

  if($this->db->{$collection}->deleteIndex($keys,$options)==TRUE)
  {
   $this->clear();
   return($this);
  }
  else
  {
   show_error("AnerroroccuredwhentryingtoremoveanindexfromMongoDBCollection",500);
 }
 }

 /**
 *--------------------------------------------------------------------------------
 *REMOVE_ALL_INDEXES
 *--------------------------------------------------------------------------------
 *
 *Removeallindexesfromacollection.
 *
 *@usage=$this->mongo_db->remove_all_index($collection);
 */

 publicfunctionremove_all_indexes($collection=""){
 if(empty($collection))
 {
   show_error("NoMongocollectionspecifiedtoremoveallindexesfrom",500);
  }

  $this->db->{$collection}->deleteIndexes();
  $this->clear();
  return($this);
 }

 /**
 *--------------------------------------------------------------------------------
 *LIST_INDEXES
 *--------------------------------------------------------------------------------
 *
 *Listsallindexesinacollection.
 *
 *@usage=$this->mongo_db->list_indexes($collection);
 */
 publicfunctionlist_indexes($collection=""){
 if(empty($collection))
 {
   show_error("NoMongocollectionspecifiedtoremoveallindexesfrom",500);
  }
  return($this->db->{$collection}->getIndexInfo());
 }

 /**
 *--------------------------------------------------------------------------------
 *DROPCOLLECTION
 *--------------------------------------------------------------------------------
 *
 *Removesthespecifiedcollectionfromthedatabase. Becarefulbecausethis
 * canhavesomeverylargeissuesinproduction!
 */

 publicfunctiondrop_collection($collection="")
 {
   if(empty($collection))
  {
     show_error("NoMongocollectionspecifiedtodropfromdatabase",500);
   }
   $this->db->{$collection}->drop();
   returnTRUE;
 }

 /**
 *--------------------------------------------------------------------------------
 *CONNECTTOMONGODB
 *--------------------------------------------------------------------------------
 *
 *EstablishaconnectiontoMongoDBusingtheconnectionstringgeneratedin
 *theconnection_string()method. If"mongo_persist_key"wassettotrueinthe
 *configfile,establishapersistentconnection. Weallowforonlythe"persist"
 *optiontobesetbecausewewanttoestablishaconnectionimmediately.
 */

 privatefunctionconnect(){
 $options=array();
 if($this->persist===TRUE)
 {
  $options["persist"]=isset($this->persist_key)&&!empty($this->persist_key)?$this->persist_key:"ci_mongo_persist";
 }

 try
 {
  $this->connection=newMongo($this->connection_string,$options);
  $this->db=$this->connection->{$this->dbname};
  return($this);
 }
 catch(MongoConnectionException$e)
 {
  show_error("UnabletoconnecttoMongoDB:{$e->getMessage()}",500);
 }
 }

 /**
 *--------------------------------------------------------------------------------
 *BUILDCONNECTIONSTRING
 *--------------------------------------------------------------------------------
 *
 *Buildtheconnectionstringfromtheconfigfile.
 */

 privatefunctionconnection_string($MONGODB_CONFIG)
 {

 $this->host=trim($MONGODB_CONFIG["HOST"]);
 $this->port=trim($MONGODB_CONFIG["PORT"]);
 $this->user=trim($MONGODB_CONFIG["USER"]);
 $this->pass=trim($MONGODB_CONFIG["PWD"]);
 $this->dbname=trim($MONGODB_CONFIG["DATABASE"]);
 $this->persist=trim($MONGODB_CONFIG["PERSIST"]);
 $this->persist_key=trim($MONGODB_CONFIG["PERSIST_KEY"]);

 $connection_string="mongodb://";

 if(empty($this->host))
 {
  show_error("TheHostmustbesettoconnecttoMongoDB",500);
 }

 if(empty($this->dbname))
 {
  show_error("TheDatabasemustbesettoconnecttoMongoDB",500);
 }

 if(!empty($this->user)&&!empty($this->pass))
 {
  $connection_string.="{$this->user}:{$this->pass}@";
 }

 if(isset($this->port)&&!empty($this->port))
 {
  $connection_string.="{$this->host}:{$this->port}/{$this->dbname}";
 }
 else
 {
  $connection_string.="{$this->host}";
 }

 $this->connection_string=trim($connection_string);
 }

 /**
 *--------------------------------------------------------------------------------
 *CLEAR
 *--------------------------------------------------------------------------------
 *
 *Resetstheclassvariablestodefaultsettings
 */

 privatefunctionclear()
 {
 $this->selects=array();
 $this->wheres=array();
 $this->limit=NULL;
 $this->offset=NULL;
 $this->sorts=array();
 }

 /**
 *--------------------------------------------------------------------------------
 *WHEREINITIALIZER
 *--------------------------------------------------------------------------------
 *
 *Preparesparametersforinsertionin$wheresarray().
 */

 privatefunctionwhere_init($param)
 {
 if(!isset($this->wheres[$param]))
 {
  $this->wheres[$param]=array();
  }
 }

 /**
 *--------------------------------------------------------------------------------
 *设置表
 *--------------------------------------------------------------------------------
 * 参数：
 * $table表名
 */
 publicfunctionset_table($table){
 $this->collection=$table;
 }

 /**
 *--------------------------------------------------------------------------------
 *获取表名
 *--------------------------------------------------------------------------------
 */
 publicfunctionget_table(){
 return$this->collection;
 }

 /**
 *--------------------------------------------------------------------------------
 *设置表排序
 *--------------------------------------------------------------------------------
 * 参数：
 * $orderby排序
 */
 publicfunctionset_orderby($orderby){
 $this->page_sorts=$orderby;
 }

 
 /**
 *--------------------------------------------------------------------------------
 *获取左边结果集
 *--------------------------------------------------------------------------------
 * 参数：
 * $left左边显示的个数
 * $last定位当前页的值
 * $size页面大小
 */
 publicfunctionget_left($left,$last,$size=PAGE_SIZE){
 if($last){
  $order=$this->nor_orderby();
  if($this->page_sorts[$this->key]==-1){
   $this->where_gt($this->key,$last);
  }else{
    $this->where_lt($this->key,$last);
  }
  return$this->limit($left*$size)->order_by($order)->get($this->collection);
 }
 }

 
 /**
 *--------------------------------------------------------------------------------
 *获取右边结果集
 *--------------------------------------------------------------------------------
 * 参数：
 * $right右边显示的个数
 * $last定位当前页的值
 * $size页面大小
 */
 publicfunctionget_right($right,$last,$size=PAGE_SIZE){
 if($last){
  if($this->page_sorts[$this->key]==-1){
   $this->where_lte($this->key,$last);
  }else{
   $this->where_gte($this->key,$last);
  }
 }
 return$this->limit($right*$size+1)->order_by($this->page_sorts)->get($this->collection);
 }

 /**
 *--------------------------------------------------------------------------------
 *设置key
 *--------------------------------------------------------------------------------
 * 参数：
 * $key设置索引主键
 */
 publicfunctionset_key($key){
 $this->key=$key;
 }

 /**
 *--------------------------------------------------------------------------------
 *求反
 *--------------------------------------------------------------------------------
 */
 privatefunctionnor_orderby(){
 foreach($this->page_sortsas$key=>$order){
  if($order==-1){
   $orderby[$key]=1;
  }else{
   $orderby[$key]=-1;
  }  
 }
 return$orderby;
 }

 /**
 *--------------------------------------------------------------------------------
 *获取上一页的值
 *--------------------------------------------------------------------------------
 * 参数：
 * $last定位当前页的值
 * $size页面大小
 */
 publicfunctionget_prev($last,$size=PAGE_SIZE){
 if($last){
  if($this->page_sorts[$this->key]==1){
   $this->where_lt($this->key,$last)->order_by(array($this->key=>-1));
  }else{
   $this->where_gt($this->key,$last)->order_by(array($this->key=>1));
  }
  $result=$this->limit($size)->get($this->collection);
 }
 return$result[$size-1][$this->key];
 }

 /**
 *--------------------------------------------------------------------------------
 *获取下一页的值
 *--------------------------------------------------------------------------------
 * 参数：
 * $last定位当前页的值
 * $size页面大小
 */
 publicfunctionget_next($last,$size=PAGE_SIZE){
 if($last){
  if($this->page_sorts[$this->key]==1){
   $this->where_gte($this->key,$last);
  }else{
   $this->where_lte($this->key,$last);
  }
 }
 $result=$this->limit($size+1)->order_by($this->page_sorts)->get($this->collection);
 return$result[$size][$this->key];
 }

 /**
 *--------------------------------------------------------------------------------
 *获取最后一页的值
 *--------------------------------------------------------------------------------
 * 参数：
 * $size页面大小
 */
 publicfunctionget_last($size=PAGE_SIZE){
 $res=$this->count($this->collection)%$size;
 $order=$this->nor_orderby();
 if($res>0){
  $result=$this->limit($res)->order_by($order)->get($this->collection);
  return$result[$res-1][$this->key];
 }else{
  $result=$this->limit($size)->order_by($order)->get($this->collection);
  return$result[$size-1][$this->key];
 }
 }

 /**
 *--------------------------------------------------------------------------------
 *分页查询
 *--------------------------------------------------------------------------------
 * 参数：
 * $last定位当前页的值
 * $size页面大小
 */
 publicfunctionpage_query($last,$size=PAGE_SIZE){
 if($last){
  if($this->page_sorts[$this->key]==1){
   $this->where_gte($this->key,$last);
  }else{
   $this->where_lte($this->key,$last);
  }
 }
 return$this->limit($size)->order_by($this->page_sorts)->get($this->collection);
 }

 /**
 *批量执行代码_插入
 *@paramString$collection
 *@param二维数组$code
 */
 publicfunctionexecute_insert($collection,$code){
 //将二维数组分成js格式
 $strcode="";
 foreach($codeas$k=>$v){
  foreach($vas$kk=>$vv){
   $strcode.="db.getCollection("".$collection."").insert({"".$kk."":"".$vv.""});";
  }   
 }
 //retrunarray([ok]=>1);
 return$this->db->execute($code); 
 }

}
?>