PHP chained syntax

Idea: The chain syntax is the object call method after the assignment operation returns an object, then you can call the method, the last method to return a specific SQL statement

<?phpclass sql{    Private $sql =array ("from" and "" ",            " where "=" ",            " order "=" ","            limit "= > "");    Public function from ($tableName) {        $this->sql[' from ']= ' from '. $tableName;        return $this;    }    Public function where ($_where= ' 1=1 ') {        $this->sql["where"]= "where". $_where;        return $this;    }    Public Function order ($_order= ' ID DESC ') {        $this->sql["order"]= "ORDER by". $_order;        return $this;    }    Public function limit ($_limit= ') {        $this->sql["Limit"]= "Limit 0,". $_limit;        return $this;    }    Public Function Select ($_select= ' * ') {        return "select". $_select. " ". (Implode ("", $this->sql));}    } $sql =new SQL (), echo $sql->from ("TestTable")->where ("Id=1")->order ("id DESC")->limit ()->select () ;//Output SELECT * from TestTable WHERE id=1 ORDER by ID DESC LIMIT 0,10?>

　　

PHP chained syntax