class MySQLDB { //MYSQL数据库操作类 //作者:熊毅 //版本:2.0(发行版) //可以自由转载,修改请通知我scxy78@yeah.net //转载请保留以上声明 //使用说明: //该类完全按照ADO的习惯书写的,用过ASP的人都觉得ASP连接数据库比PHP好用(这是我的感觉), //
class MySQLDB
{
//MYSQL数据库操作类
//作者:熊毅
//版本:2.0(发行版)
//可以自由转载,修改请通知我scxy78@yeah.net
//转载请保留以上声明
//使用说明:
//该类完全按照ADO的习惯书写的,用过ASP的人都觉得ASP连接数据库比PHP好用(这是我的感觉),
//但PHP得一个一个API地写,挺累,该类做了完全的封装
//创建类的实例时可以指定一个数据库表和选择的数据库,如:new MySQLDB("table","database");
//查询数据时Query后可以用GetValue得到相应的值,既可以是字段名也可以是已0开始的序号
//插入新值,先用AddNew后使用SetValue相应的字段名或序号和字段值,在用Update添加
//编辑时用Edit指定编辑记录的条件在使用SetValue,最后用Update添加
//在类使用过程中,sTName记录上次使用的数据库表名,当指定后可以直接使用,以后的操作默认在该表
//上进行操作,当然也可以每次指定特殊的表进行操作
//nErr指示是否操作出错,sErr记录最后一次出错的错误代码,记录了明确的有哪个函数引起的错误
//错误之处请指正
//欢迎来信与我交流编程经验:scxy78@yeah.net
//我的CSDN:用户号:scxy;呢称:小熊,请多关照
//可以自由转载,修改请通知我scxy78@yeah.net
//转载请保留以上声明
var $host="localhost"; //主机名
var $user="boot"; //用户名
var $password="oaserver"; //用户密码
var $linkid; //连接值
var $dbid; //数据库选择的结果值
var $sTName; //指定当前操作的数据库表
var $sErr; //错误代码
var $nErr; //指示是否有错误存在,0无错误,1有错误
var $nResult; //查询结果值
var $aFName; //保存FieldsName的数组
var $nRows; //查询结果中的行数
var $nCols; //查询结果中的列数
var $aNew; //添加在AddNew函数后的数据,以数组形式保存
var $NewEdit; //判断当前是否在进行添加操作,0表示没有,1表示在进行添加,2表示编辑
var $sEditCon; //指定编辑记录的条件
var $nOffset; //记录偏移量
var $EOF; //标记是否到记录集尾
var $sSQL; //最后一条执行的SQL语句
//执行Update所要用到的全局变量
var $sName; //字段名
var $sValue; //字段值AddNew时用
var $sEdit; //字段值Edit时用
function Initialize()
{
$this->nErr=0;
$this->NewEdit=0;
$this->nResult=-1;
$this->nCols=0;
$this->nRows=0;
$this->nOffset=0;
$this->EOF=true;
$this->sName="";
$this->sValue="#@!";
$this->sEdit="#@!";
unset($this->aFName);
unset($this->aNew);
}
function MySqlDB($TableName="",$database="slt") //构造函数
{
$this->Initialize();
$this->sTName=$TableName;
$this->linkid=mysql_connect($host,$user,$password);
if(!$this->linkid)
{
$this->nErr=1;
$this->sErr="MySqlDB:数据库连接出错,请启动服务!";
return;
}
$this->dbid=mysql_select_db($database);
if(!$this->dbid)
{
$this->nErr=1;
$this->sErr="MySqlDB:选择的数据库".$database."不存在!";
return;
}
}
function IsEmpty($Value)
{
if(is_string($Value)&&empty($Value))
return true;
return false;
}
function Destroy() //数据清除处理
{
mysql_query("commit");
mysql_close();
}
function PrintErr()
{
if($this->nErr==1)
{
echo($this->sErr."
");
}
else
{
echo("没有错误
");
}
}
function Execute($SQL) //直接执行SQL语句
{
if(empty($SQL))
{
$this->nErr=1;
$this->sErr="Execute:执行语句不能为空!";
return false;
}
$this->sSQL=$SQL;
if(!mysql_query($SQL))
{
$this->nErr=1;
$this->sErr="Execute:SQL语句:".$SQL."
MySql错误:".mysql_error();
return false;
}
return true;
}
function Query($TableName="",$SQL="*",$Condition="",$Order="",$Sequenc="") //在数据库里执行查询
{
$this->Initialize();
if(!empty($TableName))
$this->sTName=$TableName;
$strSQL="select ".$SQL." from ".$this->sTName;
if(!empty($Condition))
$strSQL=$strSQL." where ".$Condition;
if(!empty($Order))
$strSQL=$strSQL." order by ".$Order;
if(!empty($Sequenc))
$strSQL=$strSQL." ".$Sequenc;
$this->sSQL=$strSQL;
if(!$this->nResult=mysql_query($strSQL))
{
$this->nErr=1;
$this->sErr="Query:SQL语句:".$strSQL."
MySql错误:".mysql_error()."
";
return;
}
$this->nOffset=0;
$this->nRows=mysql_num_rows($this->nResult);
$this->nCols=mysql_num_fields($this->nResult);
if($this->nRows>0)
$this->EOF=false;
else
$this->EOF=true;
unset($this->aFName);
$this->aFName=array();
for($i=0;$inCols;$i++)
$this->aFName[$i]=strtolower(mysql_field_name($this->nResult,$i));
}
function MoveNext()
{
if($this->EOF)
{
$this->nErr=1;
$this->sErr="MoveNext:已经移到记录集末尾!";
return;
}
$this->nOffset++;
if($this->nOffset>=$this->nRows)
$this->EOF=true;
}
function MoveTo($Offset)
{
if(empty($Offset))
{
$this->nErr=1;
$this->sErr="MoveTo:必须指定偏移量! ";
return;
}
if(!$this->nResult)
{
$this->nErr=1;
$this->sErr="MoveTo:请先执行查询:Query";
return;
}
$this->nOffset=$Offset;
}
//得到指定行的指定列的值,返回字符串
//如果不指定Offset将取得下一行的值
//如果不指定nFields将取得该行的值,并已数组形式返回
function GetValue($nFields=-1,$Offset=-1)
{
if($this->nResult==-1)
{
$this->nErr=1;
$this->sErr="GetValue:请先执行Query()函数!";
return;
}
if($Offset>-1)
{
$this->nOffset=$Offset;
if($this->nOffset>=$this->nRows)
{
$this->nErr=1;
$this->sErr="GetValue:所要求的偏移量太大,无法达到!";
return;
}
}
if(!@mysql_data_seek($this->nResult,$this->nOffset))
{
$this->nErr=1;
$this->sErr="GetValue:请求不存在的记录!";
return;
}
$aResult=mysql_fetch_row($this->nResult);
if(is_int($nFields)&&$nFields>-1)
{
if($nFileds>$this->nCols)
{
$this->nErr=1;
$this->sErr="GetValue:所请求的列值大于实际的列值!";
return;
}
return $aResult[$nFields];
}
if(is_string($nFields))
{
$nFields=strtolower($nFields);
for($i=0;$inCols;$i++)
{
if($this->aFName[$i]==$nFields)
break;
}
if($i==$this->nCols)
{
$this->nErr=1;
$this->sErr="GetValue:所请求的列不存在,请仔细检查!";
return;
}
return $aResult[$i];
}
return $aResult;
}
function AddNew($TableName="") //标志开始添加数据
{
$this->Initialize();
if(!empty($TableName))
$this->sTName=$TableName;
if($this->NewEdit>0)
{
$this->nErr=1;
$this->sErr="AddNew:你正在对数据库进行添加或更新操作!";
return;
}
if(empty($this->sTName))
{
$this->nErr=1;
$this->sErr="AddNew:想要添加的数据库表为空,可以在构造时指定,也可在AddNew()时指定!";
return;
}
unset($this->aNew);
$this->aNew=array();
$this->NewEdit=1;
$strSQL="select * from ".$this->sTName;
$this->sSQL=$strSQL;
if(!$this->nResult=mysql_query($strSQL))
{
$this->nErr=1;
$this->sErr="AddNew:SQL语句:".strSQL."
MySql错误:".mysql_error();
return;
}
$this->nCols=mysql_num_fields($this->nResult);
unset($this->aFName);
$this->aFName=array();
for($i=0;$inCols;$i++)
$this->aFName[$i]=strtolower(mysql_field_name($this->nResult,$i));
}
function Edit($Condition="",$TableName="") //对指定数据库表进行编辑
{
$this->Initialize();
if(!empty($TableName))
$this->sTName=$TableName;
$this->sEditCon=$Condition;
if(empty($this->sTName))
{
$this->nErr=1;
$this->sErr="Edit:在编辑前请先指定数据库表!";
return;
}
unset($this->aNew);
$this->aNew=array();
$this->NewEdit=2;
$strSQL="select * from ".$this->sTName;
$this->sSQL=$strSQL;
if(!$this->nResult=mysql_query($strSQL))
{
$this->nErr=1;
$this->sErr="Edit:SQL语句:".strSQL."
MySql错误:".mysql_error();
return;
}
$this->nCols=mysql_num_fields($this->nResult);
unset($this->aFName);
$this->aFName=array();
for($i=0;$inCols;$i++)
$this->aFName[$i]=strtolower(mysql_field_name($this->nResult,$i));
}
function SetValue($Index,$Value) //指定数据,跟在AddNew后执行;
{
if($this->NewEdit==0)
{
$this->nErr=1;
$this->sErr="SetValue:请先执行AddNew()或者Edit()!";
return;
}
if(is_int($Index))
{
if($Index$this->nCols)
{
$this->nErr=1;
$this->sErr="SetValue:插入不存在的列值!";
return;
}
$this->aNew[$Index]=$Value;
$tmpIn=$Index;
}
elseif(is_string($Index))
{
$Index=strtolower($Index);
for($i=0;$inCols;$i++)
{
if($this->aFName[$i]==$Index)
break;
}
if($i==$this->nCols)
{
$this->nErr=1;
$this->sErr="SetValue:插入不存在的列值!";
return;
}
$this->aNew[$i]=$Value;
$tmpIn=$i;
}
if(!empty($this->sName))
$this->sName.=",";
$this->sName.=$this->aFName[$tmpIn];
//根据当前字段的类型生成相应的新值
if($this->sValue!="#@!")
$this->sValue.=",";
else
$this->sValue="";
$ftype=@mysql_field_type($this->nResult,$i);
//echo($ftype.",".$this->aNew[$i].",".$i.":".$sValue."
");
switch($ftype)
{
case "string":
case "date":
case "datetime":
$this->sValue.="\"".$this->aNew[$tmpIn]."\"";
$this->sEdit="\"".$this->aNew[$tmpIn]."\"";
break;
case "int":
case "unknown":
$this->sValue.=$this->aNew[$tmpIn];
$this->sEdit=$this->aNew[$tmpIn];
break;
default:
$this->nErr=1;
$this->sErr="Update:字段名为".$this->aFName[$tmpIn]."的".$ftype."类型目前版本不支持,请用别的方法添加数据!";
return;
}
if($this->NewEdit==2)
$this->sName.="=".$this->sEdit;
}
function Update() //存储新值到数据库
{
$strSQL="";
if($this->NewEdit==0)
{
$this->nErr=1;
$this->sErr="Update:请先执行AddNew()或者Edit(),再用SetValue()添加值!";
return;
}
if(empty($this->sValue))
{
$this->nErr=1;
$this->sErr="Update:在数据为空的情况下,不能添加或修改数据!";
return;
}
switch($this->NewEdit)
{
case 1: //添加
$strSQL="insert into ";
$strSQL.=$this->sTName;
$strSQL.=" (".$this->sName.") ";
$strSQL.="values (".$this->sValue.")";
break;
case 2: //修改
$strSQL="update ";
$strSQL.=$this->sTName;
$strSQL.=" set ";
$strSQL.=$this->sName;
if(!empty($this->sEditCon))
$strSQL.=" where ".$this->sEditCon;
break;
default:
$this->nErr=1;
$this->sErr="Update:Update()生成SQL语句出错,请检查!";
return;
}
$this->sSQL=$strSQL;
if(!$this->nResult=mysql_query($strSQL))
{
$this->nErr=1;
$this->sErr="Update:SQL语句:".$strSQL."
MySql错误:".mysql_error();
return;
}
//echo($this->sSQL."
");
//作清理工作
$this->NewEdit=0;
unset($this->aNew);
mysql_query("commit");
}
}
(责任编辑:铭铭 mingming_ky@126.com TEL:(010)68476636)

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